Merge branch 'kvm-updates/3.1' of git://git.kernel.org/pub/scm/virt/kvm/kvm

* 'kvm-updates/3.1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (143 commits) KVM: IOMMU: Disable device assignment without interrupt remapping KVM: MMU: trace mmio page fault KVM: MMU: mmio page fault support KVM: MMU: reorganize struct kvm_shadow_walk_iterator KVM: MMU: lockless walking shadow page table KVM: MMU: do not need atomicly to set/clear spte KVM: MMU: introduce the rules to modify shadow page table KVM: MMU: abstract some functions to handle fault pfn KVM: MMU: filter out the mmio pfn from the fault pfn KVM: MMU: remove bypass_guest_pf KVM: MMU: split kvm_mmu_free_page KVM: MMU: count used shadow pages on prepareing path KVM: MMU: rename 'pt_write' to 'emulate' KVM: MMU: cleanup for FNAME(fetch) KVM: MMU: optimize to handle dirty bit KVM: MMU: cache mmio info on page fault path KVM: x86: introduce vcpu_mmio_gva_to_gpa to cleanup the code KVM: MMU: do not update slot bitmap if spte is nonpresent KVM: MMU: fix walking shadow page table KVM guest: KVM Steal time registration ...
author: Linus Torvalds <torvalds@linux-foundation.org> 2011-07-24 09:07:03 -0700
committer: Linus Torvalds <torvalds@linux-foundation.org> 2011-07-24 09:07:03 -0700
commit: 5fabc487c96819dd12ddb9414835d170fd9cd6d5 (patch)
tree: 01532d492e5074b0d3add29bf92ebf9a9d161e9e /arch/x86
parent: c61264f98c1a974ee6f545f61a4ab33b141d6bda (diff)
parent: 3f68b0318bbbd61bf08478ab99a149f0d9e5156e (diff)
download: blackbird-op-linux-5fabc487c96819dd12ddb9414835d170fd9cd6d5.tar.gz
blackbird-op-linux-5fabc487c96819dd12ddb9414835d170fd9cd6d5.zip
24 files changed, 4982 insertions, 1855 deletions
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index b2127544fbe7..a67e014e4e44 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -529,6 +529,18 @@ menuconfig PARAVIRT_GUEST
 
 if PARAVIRT_GUEST
 
+config PARAVIRT_TIME_ACCOUNTING
+	bool "Paravirtual steal time accounting"
+	select PARAVIRT
+	default n
+	---help---
+	  Select this option to enable fine granularity task steal time
+	  accounting. Time spent executing other tasks in parallel with
+	  the current vCPU is discounted from the vCPU power. To account for
+	  that, there can be a small performance impact.
+
+	  If in doubt, say N here.
+
 source "arch/x86/xen/Kconfig"
 
 config KVM_CLOCK
diff --git a/arch/x86/include/asm/kvm_emulate.h b/arch/x86/include/asm/kvm_emulate.h
index 0049211959c0..6040d115ef51 100644
--- a/arch/x86/include/asm/kvm_emulate.h
+++ b/arch/x86/include/asm/kvm_emulate.h
@@ -229,7 +229,26 @@ struct read_cache {
 	unsigned long end;
 };
 
-struct decode_cache {
+struct x86_emulate_ctxt {
+	struct x86_emulate_ops *ops;
+
+	/* Register state before/after emulation. */
+	unsigned long eflags;
+	unsigned long eip; /* eip before instruction emulation */
+	/* Emulated execution mode, represented by an X86EMUL_MODE value. */
+	int mode;
+
+	/* interruptibility state, as a result of execution of STI or MOV SS */
+	int interruptibility;
+
+	bool guest_mode; /* guest running a nested guest */
+	bool perm_ok; /* do not check permissions if true */
+	bool only_vendor_specific_insn;
+
+	bool have_exception;
+	struct x86_exception exception;
+
+	/* decode cache */
 	u8 twobyte;
 	u8 b;
 	u8 intercept;
@@ -246,8 +265,6 @@ struct decode_cache {
 	unsigned int d;
 	int (*execute)(struct x86_emulate_ctxt *ctxt);
 	int (*check_perm)(struct x86_emulate_ctxt *ctxt);
-	unsigned long regs[NR_VCPU_REGS];
-	unsigned long eip;
 	/* modrm */
 	u8 modrm;
 	u8 modrm_mod;
@@ -255,34 +272,14 @@ struct decode_cache {
 	u8 modrm_rm;
 	u8 modrm_seg;
 	bool rip_relative;
+	unsigned long _eip;
+	/* Fields above regs are cleared together. */
+	unsigned long regs[NR_VCPU_REGS];
 	struct fetch_cache fetch;
 	struct read_cache io_read;
 	struct read_cache mem_read;
 };
 
-struct x86_emulate_ctxt {
-	struct x86_emulate_ops *ops;
-
-	/* Register state before/after emulation. */
-	unsigned long eflags;
-	unsigned long eip; /* eip before instruction emulation */
-	/* Emulated execution mode, represented by an X86EMUL_MODE value. */
-	int mode;
-
-	/* interruptibility state, as a result of execution of STI or MOV SS */
-	int interruptibility;
-
-	bool guest_mode; /* guest running a nested guest */
-	bool perm_ok; /* do not check permissions if true */
-	bool only_vendor_specific_insn;
-
-	bool have_exception;
-	struct x86_exception exception;
-
-	/* decode cache */
-	struct decode_cache decode;
-};
-
 /* Repeat String Operation Prefix */
 #define REPE_PREFIX	0xf3
 #define REPNE_PREFIX	0xf2
@@ -373,6 +370,5 @@ int x86_emulate_insn(struct x86_emulate_ctxt *ctxt);
 int emulator_task_switch(struct x86_emulate_ctxt *ctxt,
 			 u16 tss_selector, int reason,
 			 bool has_error_code, u32 error_code);
-int emulate_int_real(struct x86_emulate_ctxt *ctxt,
-		     struct x86_emulate_ops *ops, int irq);
+int emulate_int_real(struct x86_emulate_ctxt *ctxt, int irq);
 #endif /* _ASM_X86_KVM_X86_EMULATE_H */
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index d2ac8e2ee897..dd51c83aa5de 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -48,7 +48,7 @@
 	(~(unsigned long)(X86_CR4_VME | X86_CR4_PVI | X86_CR4_TSD | X86_CR4_DE\
 			  | X86_CR4_PSE | X86_CR4_PAE | X86_CR4_MCE     \
 			  | X86_CR4_PGE | X86_CR4_PCE | X86_CR4_OSFXSR  \
-			  | X86_CR4_OSXSAVE \
+			  | X86_CR4_OSXSAVE | X86_CR4_SMEP | X86_CR4_RDWRGSFS \
 			  | X86_CR4_OSXMMEXCPT | X86_CR4_VMXE))
 
 #define CR8_RESERVED_BITS (~(unsigned long)X86_CR8_TPR)
@@ -205,6 +205,7 @@ union kvm_mmu_page_role {
 		unsigned invalid:1;
 		unsigned nxe:1;
 		unsigned cr0_wp:1;
+		unsigned smep_andnot_wp:1;
 	};
 };
 
@@ -227,15 +228,17 @@ struct kvm_mmu_page {
 	 * in this shadow page.
 	 */
 	DECLARE_BITMAP(slot_bitmap, KVM_MEMORY_SLOTS + KVM_PRIVATE_MEM_SLOTS);
-	bool multimapped;         /* More than one parent_pte? */
 	bool unsync;
 	int root_count;          /* Currently serving as active root */
 	unsigned int unsync_children;
-	union {
-		u64 *parent_pte;               /* !multimapped */
-		struct hlist_head parent_ptes; /* multimapped, kvm_pte_chain */
-	};
+	unsigned long parent_ptes;	/* Reverse mapping for parent_pte */
 	DECLARE_BITMAP(unsync_child_bitmap, 512);
+
+#ifdef CONFIG_X86_32
+	int clear_spte_count;
+#endif
+
+	struct rcu_head rcu;
 };
 
 struct kvm_pv_mmu_op_buffer {
@@ -269,8 +272,6 @@ struct kvm_mmu {
 	gpa_t (*gva_to_gpa)(struct kvm_vcpu *vcpu, gva_t gva, u32 access,
 			    struct x86_exception *exception);
 	gpa_t (*translate_gpa)(struct kvm_vcpu *vcpu, gpa_t gpa, u32 access);
-	void (*prefetch_page)(struct kvm_vcpu *vcpu,
-			      struct kvm_mmu_page *page);
 	int (*sync_page)(struct kvm_vcpu *vcpu,
 			 struct kvm_mmu_page *sp);
 	void (*invlpg)(struct kvm_vcpu *vcpu, gva_t gva);
@@ -346,8 +347,7 @@ struct kvm_vcpu_arch {
 	 * put it here to avoid allocation */
 	struct kvm_pv_mmu_op_buffer mmu_op_buffer;
 
-	struct kvm_mmu_memory_cache mmu_pte_chain_cache;
-	struct kvm_mmu_memory_cache mmu_rmap_desc_cache;
+	struct kvm_mmu_memory_cache mmu_pte_list_desc_cache;
 	struct kvm_mmu_memory_cache mmu_page_cache;
 	struct kvm_mmu_memory_cache mmu_page_header_cache;
 
@@ -393,6 +393,15 @@ struct kvm_vcpu_arch {
 	unsigned int hw_tsc_khz;
 	unsigned int time_offset;
 	struct page *time_page;
+
+	struct {
+		u64 msr_val;
+		u64 last_steal;
+		u64 accum_steal;
+		struct gfn_to_hva_cache stime;
+		struct kvm_steal_time steal;
+	} st;
+
 	u64 last_guest_tsc;
 	u64 last_kernel_ns;
 	u64 last_tsc_nsec;
@@ -419,6 +428,11 @@ struct kvm_vcpu_arch {
 	u64 mcg_ctl;
 	u64 *mce_banks;
 
+	/* Cache MMIO info */
+	u64 mmio_gva;
+	unsigned access;
+	gfn_t mmio_gfn;
+
 	/* used for guest single stepping over the given code position */
 	unsigned long singlestep_rip;
 
@@ -441,6 +455,7 @@ struct kvm_arch {
 	unsigned int n_used_mmu_pages;
 	unsigned int n_requested_mmu_pages;
 	unsigned int n_max_mmu_pages;
+	unsigned int indirect_shadow_pages;
 	atomic_t invlpg_counter;
 	struct hlist_head mmu_page_hash[KVM_NUM_MMU_PAGES];
 	/*
@@ -477,6 +492,8 @@ struct kvm_arch {
 	u64 hv_guest_os_id;
 	u64 hv_hypercall;
 
+	atomic_t reader_counter;
+
 	#ifdef CONFIG_KVM_MMU_AUDIT
 	int audit_point;
 	#endif
@@ -559,7 +576,7 @@ struct kvm_x86_ops {
 	void (*decache_cr4_guest_bits)(struct kvm_vcpu *vcpu);
 	void (*set_cr0)(struct kvm_vcpu *vcpu, unsigned long cr0);
 	void (*set_cr3)(struct kvm_vcpu *vcpu, unsigned long cr3);
-	void (*set_cr4)(struct kvm_vcpu *vcpu, unsigned long cr4);
+	int (*set_cr4)(struct kvm_vcpu *vcpu, unsigned long cr4);
 	void (*set_efer)(struct kvm_vcpu *vcpu, u64 efer);
 	void (*get_idt)(struct kvm_vcpu *vcpu, struct desc_ptr *dt);
 	void (*set_idt)(struct kvm_vcpu *vcpu, struct desc_ptr *dt);
@@ -636,7 +653,6 @@ void kvm_mmu_module_exit(void);
 void kvm_mmu_destroy(struct kvm_vcpu *vcpu);
 int kvm_mmu_create(struct kvm_vcpu *vcpu);
 int kvm_mmu_setup(struct kvm_vcpu *vcpu);
-void kvm_mmu_set_nonpresent_ptes(u64 trap_pte, u64 notrap_pte);
 void kvm_mmu_set_mask_ptes(u64 user_mask, u64 accessed_mask,
 		u64 dirty_mask, u64 nx_mask, u64 x_mask);
 
@@ -830,11 +846,12 @@ enum {
 asmlinkage void kvm_spurious_fault(void);
 extern bool kvm_rebooting;
 
-#define __kvm_handle_fault_on_reboot(insn) \
+#define ____kvm_handle_fault_on_reboot(insn, cleanup_insn)	\
 	"666: " insn "\n\t" \
 	"668: \n\t"                           \
 	".pushsection .fixup, \"ax\" \n" \
 	"667: \n\t" \
+	cleanup_insn "\n\t"		      \
 	"cmpb $0, kvm_rebooting \n\t"	      \
 	"jne 668b \n\t"      		      \
 	__ASM_SIZE(push) " $666b \n\t"	      \
@@ -844,6 +861,9 @@ extern bool kvm_rebooting;
 	_ASM_PTR " 666b, 667b \n\t" \
 	".popsection"
 
+#define __kvm_handle_fault_on_reboot(insn)		\
+	____kvm_handle_fault_on_reboot(insn, "")
+
 #define KVM_ARCH_WANT_MMU_NOTIFIER
 int kvm_unmap_hva(struct kvm *kvm, unsigned long hva);
 int kvm_age_hva(struct kvm *kvm, unsigned long hva);
diff --git a/arch/x86/include/asm/kvm_para.h b/arch/x86/include/asm/kvm_para.h
index a427bf77a93d..734c3767cfac 100644
--- a/arch/x86/include/asm/kvm_para.h
+++ b/arch/x86/include/asm/kvm_para.h
@@ -21,6 +21,7 @@
  */
 #define KVM_FEATURE_CLOCKSOURCE2        3
 #define KVM_FEATURE_ASYNC_PF		4
+#define KVM_FEATURE_STEAL_TIME		5
 
 /* The last 8 bits are used to indicate how to interpret the flags field
  * in pvclock structure. If no bits are set, all flags are ignored.
@@ -30,10 +31,23 @@
 #define MSR_KVM_WALL_CLOCK  0x11
 #define MSR_KVM_SYSTEM_TIME 0x12
 
+#define KVM_MSR_ENABLED 1
 /* Custom MSRs falls in the range 0x4b564d00-0x4b564dff */
 #define MSR_KVM_WALL_CLOCK_NEW  0x4b564d00
 #define MSR_KVM_SYSTEM_TIME_NEW 0x4b564d01
 #define MSR_KVM_ASYNC_PF_EN 0x4b564d02
+#define MSR_KVM_STEAL_TIME  0x4b564d03
+
+struct kvm_steal_time {
+	__u64 steal;
+	__u32 version;
+	__u32 flags;
+	__u32 pad[12];
+};
+
+#define KVM_STEAL_ALIGNMENT_BITS 5
+#define KVM_STEAL_VALID_BITS ((-1ULL << (KVM_STEAL_ALIGNMENT_BITS + 1)))
+#define KVM_STEAL_RESERVED_MASK (((1 << KVM_STEAL_ALIGNMENT_BITS) - 1 ) << 1)
 
 #define KVM_MAX_MMU_OP_BATCH           32
 
@@ -178,6 +192,7 @@ void __init kvm_guest_init(void);
 void kvm_async_pf_task_wait(u32 token);
 void kvm_async_pf_task_wake(u32 token);
 u32 kvm_read_and_reset_pf_reason(void);
+extern void kvm_disable_steal_time(void);
 #else
 #define kvm_guest_init() do { } while (0)
 #define kvm_async_pf_task_wait(T) do {} while(0)
@@ -186,6 +201,11 @@ static inline u32 kvm_read_and_reset_pf_reason(void)
 {
 	return 0;
 }
+
+static inline void kvm_disable_steal_time(void)
+{
+	return;
+}
 #endif
 
 #endif /* __KERNEL__ */
diff --git a/arch/x86/include/asm/msr-index.h b/arch/x86/include/asm/msr-index.h
index d96bdb25ca3d..d52609aeeab8 100644
--- a/arch/x86/include/asm/msr-index.h
+++ b/arch/x86/include/asm/msr-index.h
@@ -441,6 +441,18 @@
 #define MSR_IA32_VMX_VMCS_ENUM          0x0000048a
 #define MSR_IA32_VMX_PROCBASED_CTLS2    0x0000048b
 #define MSR_IA32_VMX_EPT_VPID_CAP       0x0000048c
+#define MSR_IA32_VMX_TRUE_PINBASED_CTLS  0x0000048d
+#define MSR_IA32_VMX_TRUE_PROCBASED_CTLS 0x0000048e
+#define MSR_IA32_VMX_TRUE_EXIT_CTLS      0x0000048f
+#define MSR_IA32_VMX_TRUE_ENTRY_CTLS     0x00000490
+
+/* VMX_BASIC bits and bitmasks */
+#define VMX_BASIC_VMCS_SIZE_SHIFT	32
+#define VMX_BASIC_64		0x0001000000000000LLU
+#define VMX_BASIC_MEM_TYPE_SHIFT	50
+#define VMX_BASIC_MEM_TYPE_MASK	0x003c000000000000LLU
+#define VMX_BASIC_MEM_TYPE_WB	6LLU
+#define VMX_BASIC_INOUT		0x0040000000000000LLU
 
 /* AMD-V MSRs */
 
diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h
index ebbc4d8ab170..a7d2db9a74fb 100644
--- a/arch/x86/include/asm/paravirt.h
+++ b/arch/x86/include/asm/paravirt.h
@@ -230,6 +230,15 @@ static inline unsigned long long paravirt_sched_clock(void)
 	return PVOP_CALL0(unsigned long long, pv_time_ops.sched_clock);
 }
 
+struct jump_label_key;
+extern struct jump_label_key paravirt_steal_enabled;
+extern struct jump_label_key paravirt_steal_rq_enabled;
+
+static inline u64 paravirt_steal_clock(int cpu)
+{
+	return PVOP_CALL1(u64, pv_time_ops.steal_clock, cpu);
+}
+
 static inline unsigned long long paravirt_read_pmc(int counter)
 {
 	return PVOP_CALL1(u64, pv_cpu_ops.read_pmc, counter);
diff --git a/arch/x86/include/asm/paravirt_types.h b/arch/x86/include/asm/paravirt_types.h
index 82885099c869..2c7652163111 100644
--- a/arch/x86/include/asm/paravirt_types.h
+++ b/arch/x86/include/asm/paravirt_types.h
@@ -89,6 +89,7 @@ struct pv_lazy_ops {
 
 struct pv_time_ops {
 	unsigned long long (*sched_clock)(void);
+	unsigned long long (*steal_clock)(int cpu);
 	unsigned long (*get_tsc_khz)(void);
 };
 
diff --git a/arch/x86/include/asm/processor-flags.h b/arch/x86/include/asm/processor-flags.h
index 59ab4dffa377..2dddb317bb39 100644
--- a/arch/x86/include/asm/processor-flags.h
+++ b/arch/x86/include/asm/processor-flags.h
@@ -59,6 +59,7 @@
 #define X86_CR4_OSFXSR	0x00000200 /* enable fast FPU save and restore */
 #define X86_CR4_OSXMMEXCPT 0x00000400 /* enable unmasked SSE exceptions */
 #define X86_CR4_VMXE	0x00002000 /* enable VMX virtualization */
+#define X86_CR4_RDWRGSFS 0x00010000 /* enable RDWRGSFS support */
 #define X86_CR4_OSXSAVE 0x00040000 /* enable xsave and xrestore */
 #define X86_CR4_SMEP	0x00100000 /* enable SMEP support */
 
diff --git a/arch/x86/include/asm/vmx.h b/arch/x86/include/asm/vmx.h
index 84471b810460..2caf290e9895 100644
--- a/arch/x86/include/asm/vmx.h
+++ b/arch/x86/include/asm/vmx.h
@@ -132,6 +132,8 @@ enum vmcs_field {
 	GUEST_IA32_PAT_HIGH		= 0x00002805,
 	GUEST_IA32_EFER			= 0x00002806,
 	GUEST_IA32_EFER_HIGH		= 0x00002807,
+	GUEST_IA32_PERF_GLOBAL_CTRL	= 0x00002808,
+	GUEST_IA32_PERF_GLOBAL_CTRL_HIGH= 0x00002809,
 	GUEST_PDPTR0                    = 0x0000280a,
 	GUEST_PDPTR0_HIGH               = 0x0000280b,
 	GUEST_PDPTR1                    = 0x0000280c,
@@ -144,6 +146,8 @@ enum vmcs_field {
 	HOST_IA32_PAT_HIGH		= 0x00002c01,
 	HOST_IA32_EFER			= 0x00002c02,
 	HOST_IA32_EFER_HIGH		= 0x00002c03,
+	HOST_IA32_PERF_GLOBAL_CTRL	= 0x00002c04,
+	HOST_IA32_PERF_GLOBAL_CTRL_HIGH	= 0x00002c05,
 	PIN_BASED_VM_EXEC_CONTROL       = 0x00004000,
 	CPU_BASED_VM_EXEC_CONTROL       = 0x00004002,
 	EXCEPTION_BITMAP                = 0x00004004,
@@ -426,4 +430,43 @@ struct vmx_msr_entry {
 	u64 value;
 } __aligned(16);
 
+/*
+ * Exit Qualifications for entry failure during or after loading guest state
+ */
+#define ENTRY_FAIL_DEFAULT		0
+#define ENTRY_FAIL_PDPTE		2
+#define ENTRY_FAIL_NMI			3
+#define ENTRY_FAIL_VMCS_LINK_PTR	4
+
+/*
+ * VM-instruction error numbers
+ */
+enum vm_instruction_error_number {
+	VMXERR_VMCALL_IN_VMX_ROOT_OPERATION = 1,
+	VMXERR_VMCLEAR_INVALID_ADDRESS = 2,
+	VMXERR_VMCLEAR_VMXON_POINTER = 3,
+	VMXERR_VMLAUNCH_NONCLEAR_VMCS = 4,
+	VMXERR_VMRESUME_NONLAUNCHED_VMCS = 5,
+	VMXERR_VMRESUME_AFTER_VMXOFF = 6,
+	VMXERR_ENTRY_INVALID_CONTROL_FIELD = 7,
+	VMXERR_ENTRY_INVALID_HOST_STATE_FIELD = 8,
+	VMXERR_VMPTRLD_INVALID_ADDRESS = 9,
+	VMXERR_VMPTRLD_VMXON_POINTER = 10,
+	VMXERR_VMPTRLD_INCORRECT_VMCS_REVISION_ID = 11,
+	VMXERR_UNSUPPORTED_VMCS_COMPONENT = 12,
+	VMXERR_VMWRITE_READ_ONLY_VMCS_COMPONENT = 13,
+	VMXERR_VMXON_IN_VMX_ROOT_OPERATION = 15,
+	VMXERR_ENTRY_INVALID_EXECUTIVE_VMCS_POINTER = 16,
+	VMXERR_ENTRY_NONLAUNCHED_EXECUTIVE_VMCS = 17,
+	VMXERR_ENTRY_EXECUTIVE_VMCS_POINTER_NOT_VMXON_POINTER = 18,
+	VMXERR_VMCALL_NONCLEAR_VMCS = 19,
+	VMXERR_VMCALL_INVALID_VM_EXIT_CONTROL_FIELDS = 20,
+	VMXERR_VMCALL_INCORRECT_MSEG_REVISION_ID = 22,
+	VMXERR_VMXOFF_UNDER_DUAL_MONITOR_TREATMENT_OF_SMIS_AND_SMM = 23,
+	VMXERR_VMCALL_INVALID_SMM_MONITOR_FEATURES = 24,
+	VMXERR_ENTRY_INVALID_VM_EXECUTION_CONTROL_FIELDS_IN_EXECUTIVE_VMCS = 25,
+	VMXERR_ENTRY_EVENTS_BLOCKED_BY_MOV_SS = 26,
+	VMXERR_INVALID_OPERAND_TO_INVEPT_INVVPID = 28,
+};
+
 #endif
diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c
index 33c07b0b122e..a9c2116001d6 100644
--- a/arch/x86/kernel/kvm.c
+++ b/arch/x86/kernel/kvm.c
@@ -51,6 +51,15 @@ static int parse_no_kvmapf(char *arg)
 
 early_param("no-kvmapf", parse_no_kvmapf);
 
+static int steal_acc = 1;
+static int parse_no_stealacc(char *arg)
+{
+        steal_acc = 0;
+        return 0;
+}
+
+early_param("no-steal-acc", parse_no_stealacc);
+
 struct kvm_para_state {
 	u8 mmu_queue[MMU_QUEUE_SIZE];
 	int mmu_queue_len;
@@ -58,6 +67,8 @@ struct kvm_para_state {
 
 static DEFINE_PER_CPU(struct kvm_para_state, para_state);
 static DEFINE_PER_CPU(struct kvm_vcpu_pv_apf_data, apf_reason) __aligned(64);
+static DEFINE_PER_CPU(struct kvm_steal_time, steal_time) __aligned(64);
+static int has_steal_clock = 0;
 
 static struct kvm_para_state *kvm_para_state(void)
 {
@@ -441,6 +452,21 @@ static void __init paravirt_ops_setup(void)
 #endif
 }
 
+static void kvm_register_steal_time(void)
+{
+	int cpu = smp_processor_id();
+	struct kvm_steal_time *st = &per_cpu(steal_time, cpu);
+
+	if (!has_steal_clock)
+		return;
+
+	memset(st, 0, sizeof(*st));
+
+	wrmsrl(MSR_KVM_STEAL_TIME, (__pa(st) | KVM_MSR_ENABLED));
+	printk(KERN_INFO "kvm-stealtime: cpu %d, msr %lx\n",
+		cpu, __pa(st));
+}
+
 void __cpuinit kvm_guest_cpu_init(void)
 {
 	if (!kvm_para_available())
@@ -457,6 +483,9 @@ void __cpuinit kvm_guest_cpu_init(void)
 		printk(KERN_INFO"KVM setup async PF for cpu %d\n",
 		       smp_processor_id());
 	}
+
+	if (has_steal_clock)
+		kvm_register_steal_time();
 }
 
 static void kvm_pv_disable_apf(void *unused)
@@ -483,6 +512,31 @@ static struct notifier_block kvm_pv_reboot_nb = {
 	.notifier_call = kvm_pv_reboot_notify,
 };
 
+static u64 kvm_steal_clock(int cpu)
+{
+	u64 steal;
+	struct kvm_steal_time *src;
+	int version;
+
+	src = &per_cpu(steal_time, cpu);
+	do {
+		version = src->version;
+		rmb();
+		steal = src->steal;
+		rmb();
+	} while ((version & 1) || (version != src->version));
+
+	return steal;
+}
+
+void kvm_disable_steal_time(void)
+{
+	if (!has_steal_clock)
+		return;
+
+	wrmsr(MSR_KVM_STEAL_TIME, 0, 0);
+}
+
 #ifdef CONFIG_SMP
 static void __init kvm_smp_prepare_boot_cpu(void)
 {
@@ -500,6 +554,7 @@ static void __cpuinit kvm_guest_cpu_online(void *dummy)
 
 static void kvm_guest_cpu_offline(void *dummy)
 {
+	kvm_disable_steal_time();
 	kvm_pv_disable_apf(NULL);
 	apf_task_wake_all();
 }
@@ -548,6 +603,11 @@ void __init kvm_guest_init(void)
 	if (kvm_para_has_feature(KVM_FEATURE_ASYNC_PF))
 		x86_init.irqs.trap_init = kvm_apf_trap_init;
 
+	if (kvm_para_has_feature(KVM_FEATURE_STEAL_TIME)) {
+		has_steal_clock = 1;
+		pv_time_ops.steal_clock = kvm_steal_clock;
+	}
+
 #ifdef CONFIG_SMP
 	smp_ops.smp_prepare_boot_cpu = kvm_smp_prepare_boot_cpu;
 	register_cpu_notifier(&kvm_cpu_notifier);
@@ -555,3 +615,15 @@ void __init kvm_guest_init(void)
 	kvm_guest_cpu_init();
 #endif
 }
+
+static __init int activate_jump_labels(void)
+{
+	if (has_steal_clock) {
+		jump_label_inc(&paravirt_steal_enabled);
+		if (steal_acc)
+			jump_label_inc(&paravirt_steal_rq_enabled);
+	}
+
+	return 0;
+}
+arch_initcall(activate_jump_labels);
diff --git a/arch/x86/kernel/kvmclock.c b/arch/x86/kernel/kvmclock.c
index 6389a6bca11b..c1a0188e29ae 100644
--- a/arch/x86/kernel/kvmclock.c
+++ b/arch/x86/kernel/kvmclock.c
@@ -160,6 +160,7 @@ static void __cpuinit kvm_setup_secondary_clock(void)
 static void kvm_crash_shutdown(struct pt_regs *regs)
 {
 	native_write_msr(msr_kvm_system_time, 0, 0);
+	kvm_disable_steal_time();
 	native_machine_crash_shutdown(regs);
 }
 #endif
@@ -167,6 +168,7 @@ static void kvm_crash_shutdown(struct pt_regs *regs)
 static void kvm_shutdown(void)
 {
 	native_write_msr(msr_kvm_system_time, 0, 0);
+	kvm_disable_steal_time();
 	native_machine_shutdown();
 }
 
diff --git a/arch/x86/kernel/paravirt.c b/arch/x86/kernel/paravirt.c
index 869e1aeeb71b..613a7931ecc1 100644
--- a/arch/x86/kernel/paravirt.c
+++ b/arch/x86/kernel/paravirt.c
@@ -202,6 +202,14 @@ static void native_flush_tlb_single(unsigned long addr)
 	__native_flush_tlb_single(addr);
 }
 
+struct jump_label_key paravirt_steal_enabled;
+struct jump_label_key paravirt_steal_rq_enabled;
+
+static u64 native_steal_clock(int cpu)
+{
+	return 0;
+}
+
 /* These are in entry.S */
 extern void native_iret(void);
 extern void native_irq_enable_sysexit(void);
@@ -307,6 +315,7 @@ struct pv_init_ops pv_init_ops = {
 
 struct pv_time_ops pv_time_ops = {
 	.sched_clock = native_sched_clock,
+	.steal_clock = native_steal_clock,
 };
 
 struct pv_irq_ops pv_irq_ops = {
diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig
index 65cf8233d25c..988724b236b6 100644
--- a/arch/x86/kvm/Kconfig
+++ b/arch/x86/kvm/Kconfig
@@ -31,6 +31,7 @@ config KVM
 	select KVM_ASYNC_PF
 	select USER_RETURN_NOTIFIER
 	select KVM_MMIO
+	select TASK_DELAY_ACCT
 	---help---
 	  Support hosting fully virtualized guest machines using hardware
 	  virtualization extensions.  You will need a fairly recent
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index adc98675cda0..6f08bc940fa8 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -407,76 +407,59 @@ struct gprefix {
 		}							\
 	} while (0)
 
-/* Fetch next part of the instruction being emulated. */
-#define insn_fetch(_type, _size, _eip)                                  \
-({	unsigned long _x;						\
-	rc = do_insn_fetch(ctxt, ops, (_eip), &_x, (_size));		\
-	if (rc != X86EMUL_CONTINUE)					\
-		goto done;						\
-	(_eip) += (_size);						\
-	(_type)_x;							\
-})
-
-#define insn_fetch_arr(_arr, _size, _eip)				\
-({	rc = do_insn_fetch(ctxt, ops, (_eip), _arr, (_size));		\
-	if (rc != X86EMUL_CONTINUE)					\
-		goto done;						\
-	(_eip) += (_size);						\
-})
-
 static int emulator_check_intercept(struct x86_emulate_ctxt *ctxt,
 				    enum x86_intercept intercept,
 				    enum x86_intercept_stage stage)
 {
 	struct x86_instruction_info info = {
 		.intercept  = intercept,
-		.rep_prefix = ctxt->decode.rep_prefix,
-		.modrm_mod  = ctxt->decode.modrm_mod,
-		.modrm_reg  = ctxt->decode.modrm_reg,
-		.modrm_rm   = ctxt->decode.modrm_rm,
-		.src_val    = ctxt->decode.src.val64,
-		.src_bytes  = ctxt->decode.src.bytes,
-		.dst_bytes  = ctxt->decode.dst.bytes,
-		.ad_bytes   = ctxt->decode.ad_bytes,
+		.rep_prefix = ctxt->rep_prefix,
+		.modrm_mod  = ctxt->modrm_mod,
+		.modrm_reg  = ctxt->modrm_reg,
+		.modrm_rm   = ctxt->modrm_rm,
+		.src_val    = ctxt->src.val64,
+		.src_bytes  = ctxt->src.bytes,
+		.dst_bytes  = ctxt->dst.bytes,
+		.ad_bytes   = ctxt->ad_bytes,
 		.next_rip   = ctxt->eip,
 	};
 
 	return ctxt->ops->intercept(ctxt, &info, stage);
 }
 
-static inline unsigned long ad_mask(struct decode_cache *c)
+static inline unsigned long ad_mask(struct x86_emulate_ctxt *ctxt)
 {
-	return (1UL << (c->ad_bytes << 3)) - 1;
+	return (1UL << (ctxt->ad_bytes << 3)) - 1;
 }
 
 /* Access/update address held in a register, based on addressing mode. */
 static inline unsigned long
-address_mask(struct decode_cache *c, unsigned long reg)
+address_mask(struct x86_emulate_ctxt *ctxt, unsigned long reg)
 {
-	if (c->ad_bytes == sizeof(unsigned long))
+	if (ctxt->ad_bytes == sizeof(unsigned long))
 		return reg;
 	else
-		return reg & ad_mask(c);
+		return reg & ad_mask(ctxt);
 }
 
 static inline unsigned long
-register_address(struct decode_cache *c, unsigned long reg)
+register_address(struct x86_emulate_ctxt *ctxt, unsigned long reg)
 {
-	return address_mask(c, reg);
+	return address_mask(ctxt, reg);
 }
 
 static inline void
-register_address_increment(struct decode_cache *c, unsigned long *reg, int inc)
+register_address_increment(struct x86_emulate_ctxt *ctxt, unsigned long *reg, int inc)
 {
-	if (c->ad_bytes == sizeof(unsigned long))
+	if (ctxt->ad_bytes == sizeof(unsigned long))
 		*reg += inc;
 	else
-		*reg = (*reg & ~ad_mask(c)) | ((*reg + inc) & ad_mask(c));
+		*reg = (*reg & ~ad_mask(ctxt)) | ((*reg + inc) & ad_mask(ctxt));
 }
 
-static inline void jmp_rel(struct decode_cache *c, int rel)
+static inline void jmp_rel(struct x86_emulate_ctxt *ctxt, int rel)
 {
-	register_address_increment(c, &c->eip, rel);
+	register_address_increment(ctxt, &ctxt->_eip, rel);
 }
 
 static u32 desc_limit_scaled(struct desc_struct *desc)
@@ -486,28 +469,26 @@ static u32 desc_limit_scaled(struct desc_struct *desc)
 	return desc->g ? (limit << 12) | 0xfff : limit;
 }
 
-static void set_seg_override(struct decode_cache *c, int seg)
+static void set_seg_override(struct x86_emulate_ctxt *ctxt, int seg)
 {
-	c->has_seg_override = true;
-	c->seg_override = seg;
+	ctxt->has_seg_override = true;
+	ctxt->seg_override = seg;
 }
 
-static unsigned long seg_base(struct x86_emulate_ctxt *ctxt,
-			      struct x86_emulate_ops *ops, int seg)
+static unsigned long seg_base(struct x86_emulate_ctxt *ctxt, int seg)
 {
 	if (ctxt->mode == X86EMUL_MODE_PROT64 && seg < VCPU_SREG_FS)
 		return 0;
 
-	return ops->get_cached_segment_base(ctxt, seg);
+	return ctxt->ops->get_cached_segment_base(ctxt, seg);
 }
 
-static unsigned seg_override(struct x86_emulate_ctxt *ctxt,
-			     struct decode_cache *c)
+static unsigned seg_override(struct x86_emulate_ctxt *ctxt)
 {
-	if (!c->has_seg_override)
+	if (!ctxt->has_seg_override)
 		return 0;
 
-	return c->seg_override;
+	return ctxt->seg_override;
 }
 
 static int emulate_exception(struct x86_emulate_ctxt *ctxt, int vec,
@@ -579,7 +560,6 @@ static int __linearize(struct x86_emulate_ctxt *ctxt,
 		     unsigned size, bool write, bool fetch,
 		     ulong *linear)
 {
-	struct decode_cache *c = &ctxt->decode;
 	struct desc_struct desc;
 	bool usable;
 	ulong la;
@@ -587,7 +567,7 @@ static int __linearize(struct x86_emulate_ctxt *ctxt,
 	u16 sel;
 	unsigned cpl, rpl;
 
-	la = seg_base(ctxt, ctxt->ops, addr.seg) + addr.ea;
+	la = seg_base(ctxt, addr.seg) + addr.ea;
 	switch (ctxt->mode) {
 	case X86EMUL_MODE_REAL:
 		break;
@@ -637,7 +617,7 @@ static int __linearize(struct x86_emulate_ctxt *ctxt,
 		}
 		break;
 	}
-	if (fetch ? ctxt->mode != X86EMUL_MODE_PROT64 : c->ad_bytes != 8)
+	if (fetch ? ctxt->mode != X86EMUL_MODE_PROT64 : ctxt->ad_bytes != 8)
 		la &= (u32)-1;
 	*linear = la;
 	return X86EMUL_CONTINUE;
@@ -671,11 +651,10 @@ static int segmented_read_std(struct x86_emulate_ctxt *ctxt,
 	return ctxt->ops->read_std(ctxt, linear, data, size, &ctxt->exception);
 }
 
-static int do_fetch_insn_byte(struct x86_emulate_ctxt *ctxt,
-			      struct x86_emulate_ops *ops,
+static int do_insn_fetch_byte(struct x86_emulate_ctxt *ctxt,
 			      unsigned long eip, u8 *dest)
 {
-	struct fetch_cache *fc = &ctxt->decode.fetch;
+	struct fetch_cache *fc = &ctxt->fetch;
 	int rc;
 	int size, cur_size;
 
@@ -687,8 +666,8 @@ static int do_fetch_insn_byte(struct x86_emulate_ctxt *ctxt,
 		rc = __linearize(ctxt, addr, size, false, true, &linear);
 		if (rc != X86EMUL_CONTINUE)
 			return rc;
-		rc = ops->fetch(ctxt, linear, fc->data + cur_size,
-				size, &ctxt->exception);
+		rc = ctxt->ops->fetch(ctxt, linear, fc->data + cur_size,
+				      size, &ctxt->exception);
 		if (rc != X86EMUL_CONTINUE)
 			return rc;
 		fc->end += size;
@@ -698,7 +677,6 @@ static int do_fetch_insn_byte(struct x86_emulate_ctxt *ctxt,
 }
 
 static int do_insn_fetch(struct x86_emulate_ctxt *ctxt,
-			 struct x86_emulate_ops *ops,
 			 unsigned long eip, void *dest, unsigned size)
 {
 	int rc;
@@ -707,13 +685,30 @@ static int do_insn_fetch(struct x86_emulate_ctxt *ctxt,
 	if (eip + size - ctxt->eip > 15)
 		return X86EMUL_UNHANDLEABLE;
 	while (size--) {
-		rc = do_fetch_insn_byte(ctxt, ops, eip++, dest++);
+		rc = do_insn_fetch_byte(ctxt, eip++, dest++);
 		if (rc != X86EMUL_CONTINUE)
 			return rc;
 	}
 	return X86EMUL_CONTINUE;
 }
 
+/* Fetch next part of the instruction being emulated. */
+#define insn_fetch(_type, _size, _eip)					\
+({	unsigned long _x;						\
+	rc = do_insn_fetch(ctxt, (_eip), &_x, (_size));			\
+	if (rc != X86EMUL_CONTINUE)					\
+		goto done;						\
+	(_eip) += (_size);						\
+	(_type)_x;							\
+})
+
+#define insn_fetch_arr(_arr, _size, _eip)				\
+({	rc = do_insn_fetch(ctxt, (_eip), _arr, (_size));		\
+	if (rc != X86EMUL_CONTINUE)					\
+		goto done;						\
+	(_eip) += (_size);						\
+})
+
 /*
  * Given the 'reg' portion of a ModRM byte, and a register block, return a
  * pointer into the block that addresses the relevant register.
@@ -857,16 +852,15 @@ static void write_sse_reg(struct x86_emulate_ctxt *ctxt, sse128_t *data,
 
 static void decode_register_operand(struct x86_emulate_ctxt *ctxt,
 				    struct operand *op,
-				    struct decode_cache *c,
 				    int inhibit_bytereg)
 {
-	unsigned reg = c->modrm_reg;
-	int highbyte_regs = c->rex_prefix == 0;
+	unsigned reg = ctxt->modrm_reg;
+	int highbyte_regs = ctxt->rex_prefix == 0;
 
-	if (!(c->d & ModRM))
-		reg = (c->b & 7) | ((c->rex_prefix & 1) << 3);
+	if (!(ctxt->d & ModRM))
+		reg = (ctxt->b & 7) | ((ctxt->rex_prefix & 1) << 3);
 
-	if (c->d & Sse) {
+	if (ctxt->d & Sse) {
 		op->type = OP_XMM;
 		op->bytes = 16;
 		op->addr.xmm = reg;
@@ -875,49 +869,47 @@ static void decode_register_operand(struct x86_emulate_ctxt *ctxt,
 	}
 
 	op->type = OP_REG;
-	if ((c->d & ByteOp) && !inhibit_bytereg) {
-		op->addr.reg = decode_register(reg, c->regs, highbyte_regs);
+	if ((ctxt->d & ByteOp) && !inhibit_bytereg) {
+		op->addr.reg = decode_register(reg, ctxt->regs, highbyte_regs);
 		op->bytes = 1;
 	} else {
-		op->addr.reg = decode_register(reg, c->regs, 0);
-		op->bytes = c->op_bytes;
+		op->addr.reg = decode_register(reg, ctxt->regs, 0);
+		op->bytes = ctxt->op_bytes;
 	}
 	fetch_register_operand(op);
 	op->orig_val = op->val;
 }
 
 static int decode_modrm(struct x86_emulate_ctxt *ctxt,
-			struct x86_emulate_ops *ops,
 			struct operand *op)
 {
-	struct decode_cache *c = &ctxt->decode;
 	u8 sib;
 	int index_reg = 0, base_reg = 0, scale;
 	int rc = X86EMUL_CONTINUE;
 	ulong modrm_ea = 0;
 
-	if (c->rex_prefix) {
-		c->modrm_reg = (c->rex_prefix & 4) << 1;	/* REX.R */
-		index_reg = (c->rex_prefix & 2) << 2; /* REX.X */
-		c->modrm_rm = base_reg = (c->rex_prefix & 1) << 3; /* REG.B */
+	if (ctxt->rex_prefix) {
+		ctxt->modrm_reg = (ctxt->rex_prefix & 4) << 1;	/* REX.R */
+		index_reg = (ctxt->rex_prefix & 2) << 2; /* REX.X */
+		ctxt->modrm_rm = base_reg = (ctxt->rex_prefix & 1) << 3; /* REG.B */
 	}
 
-	c->modrm = insn_fetch(u8, 1, c->eip);
-	c->modrm_mod |= (c->modrm & 0xc0) >> 6;
-	c->modrm_reg |= (c->modrm & 0x38) >> 3;
-	c->modrm_rm |= (c->modrm & 0x07);
-	c->modrm_seg = VCPU_SREG_DS;
+	ctxt->modrm = insn_fetch(u8, 1, ctxt->_eip);
+	ctxt->modrm_mod |= (ctxt->modrm & 0xc0) >> 6;
+	ctxt->modrm_reg |= (ctxt->modrm & 0x38) >> 3;
+	ctxt->modrm_rm |= (ctxt->modrm & 0x07);
+	ctxt->modrm_seg = VCPU_SREG_DS;
 
-	if (c->modrm_mod == 3) {
+	if (ctxt->modrm_mod == 3) {
 		op->type = OP_REG;
-		op->bytes = (c->d & ByteOp) ? 1 : c->op_bytes;
-		op->addr.reg = decode_register(c->modrm_rm,
-					       c->regs, c->d & ByteOp);
-		if (c->d & Sse) {
+		op->bytes = (ctxt->d & ByteOp) ? 1 : ctxt->op_bytes;
+		op->addr.reg = decode_register(ctxt->modrm_rm,
+					       ctxt->regs, ctxt->d & ByteOp);
+		if (ctxt->d & Sse) {
 			op->type = OP_XMM;
 			op->bytes = 16;
-			op->addr.xmm = c->modrm_rm;
-			read_sse_reg(ctxt, &op->vec_val, c->modrm_rm);
+			op->addr.xmm = ctxt->modrm_rm;
+			read_sse_reg(ctxt, &op->vec_val, ctxt->modrm_rm);
 			return rc;
 		}
 		fetch_register_operand(op);
@@ -926,26 +918,26 @@ static int decode_modrm(struct x86_emulate_ctxt *ctxt,
 
 	op->type = OP_MEM;
 
-	if (c->ad_bytes == 2) {
-		unsigned bx = c->regs[VCPU_REGS_RBX];
-		unsigned bp = c->regs[VCPU_REGS_RBP];
-		unsigned si = c->regs[VCPU_REGS_RSI];
-		unsigned di = c->regs[VCPU_REGS_RDI];
+	if (ctxt->ad_bytes == 2) {
+		unsigned bx = ctxt->regs[VCPU_REGS_RBX];
+		unsigned bp = ctxt->regs[VCPU_REGS_RBP];
+		unsigned si = ctxt->regs[VCPU_REGS_RSI];
+		unsigned di = ctxt->regs[VCPU_REGS_RDI];
 
 		/* 16-bit ModR/M decode. */
-		switch (c->modrm_mod) {
+		switch (ctxt->modrm_mod) {
 		case 0:
-			if (c->modrm_rm == 6)
-				modrm_ea += insn_fetch(u16, 2, c->eip);
+			if (ctxt->modrm_rm == 6)
+				modrm_ea += insn_fetch(u16, 2, ctxt->_eip);
 			break;
 		case 1:
-			modrm_ea += insn_fetch(s8, 1, c->eip);
+			modrm_ea += insn_fetch(s8, 1, ctxt->_eip);
 			break;
 		case 2:
-			modrm_ea += insn_fetch(u16, 2, c->eip);
+			modrm_ea += insn_fetch(u16, 2, ctxt->_eip);
 			break;
 		}
-		switch (c->modrm_rm) {
+		switch (ctxt->modrm_rm) {
 		case 0:
 			modrm_ea += bx + si;
 			break;
@@ -965,46 +957,46 @@ static int decode_modrm(struct x86_emulate_ctxt *ctxt,
 			modrm_ea += di;
 			break;
 		case 6:
-			if (c->modrm_mod != 0)
+			if (ctxt->modrm_mod != 0)
 				modrm_ea += bp;
 			break;
 		case 7:
 			modrm_ea += bx;
 			break;
 		}
-		if (c->modrm_rm == 2 || c->modrm_rm == 3 ||
-		    (c->modrm_rm == 6 && c->modrm_mod != 0))
-			c->modrm_seg = VCPU_SREG_SS;
+		if (ctxt->modrm_rm == 2 || ctxt->modrm_rm == 3 ||
+		    (ctxt->modrm_rm == 6 && ctxt->modrm_mod != 0))
+			ctxt->modrm_seg = VCPU_SREG_SS;
 		modrm_ea = (u16)modrm_ea;
 	} else {
 		/* 32/64-bit ModR/M decode. */
-		if ((c->modrm_rm & 7) == 4) {
-			sib = insn_fetch(u8, 1, c->eip);
+		if ((ctxt->modrm_rm & 7) == 4) {
+			sib = insn_fetch(u8, 1, ctxt->_eip);
 			index_reg |= (sib >> 3) & 7;
 			base_reg |= sib & 7;
 			scale = sib >> 6;
 
-			if ((base_reg & 7) == 5 && c->modrm_mod == 0)
-				modrm_ea += insn_fetch(s32, 4, c->eip);
+			if ((base_reg & 7) == 5 && ctxt->modrm_mod == 0)
+				modrm_ea += insn_fetch(s32, 4, ctxt->_eip);
 			else
-				modrm_ea += c->regs[base_reg];
+				modrm_ea += ctxt->regs[base_reg];
 			if (index_reg != 4)
-				modrm_ea += c->regs[index_reg] << scale;
-		} else if ((c->modrm_rm & 7) == 5 && c->modrm_mod == 0) {
+				modrm_ea += ctxt->regs[index_reg] << scale;
+		} else if ((ctxt->modrm_rm & 7) == 5 && ctxt->modrm_mod == 0) {
 			if (ctxt->mode == X86EMUL_MODE_PROT64)
-				c->rip_relative = 1;
+				ctxt->rip_relative = 1;
 		} else
-			modrm_ea += c->regs[c->modrm_rm];
-		switch (c->modrm_mod) {
+			modrm_ea += ctxt->regs[ctxt->modrm_rm];
+		switch (ctxt->modrm_mod) {
 		case 0:
-			if (c->modrm_rm == 5)
-				modrm_ea += insn_fetch(s32, 4, c->eip);
+			if (ctxt->modrm_rm == 5)
+				modrm_ea += insn_fetch(s32, 4, ctxt->_eip);
 			break;
 		case 1:
-			modrm_ea += insn_fetch(s8, 1, c->eip);
+			modrm_ea += insn_fetch(s8, 1, ctxt->_eip);
 			break;
 		case 2:
-			modrm_ea += insn_fetch(s32, 4, c->eip);
+			modrm_ea += insn_fetch(s32, 4, ctxt->_eip);
 			break;
 		}
 	}
@@ -1014,53 +1006,50 @@ done:
 }
 
 static int decode_abs(struct x86_emulate_ctxt *ctxt,
-		      struct x86_emulate_ops *ops,
 		      struct operand *op)
 {
-	struct decode_cache *c = &ctxt->decode;
 	int rc = X86EMUL_CONTINUE;
 
 	op->type = OP_MEM;
-	switch (c->ad_bytes) {
+	switch (ctxt->ad_bytes) {
 	case 2:
-		op->addr.mem.ea = insn_fetch(u16, 2, c->eip);
+		op->addr.mem.ea = insn_fetch(u16, 2, ctxt->_eip);
 		break;
 	case 4:
-		op->addr.mem.ea = insn_fetch(u32, 4, c->eip);
+		op->addr.mem.ea = insn_fetch(u32, 4, ctxt->_eip);
 		break;
 	case 8:
-		op->addr.mem.ea = insn_fetch(u64, 8, c->eip);
+		op->addr.mem.ea = insn_fetch(u64, 8, ctxt->_eip);
 		break;
 	}
 done:
 	return rc;
 }
 
-static void fetch_bit_operand(struct decode_cache *c)
+static void fetch_bit_operand(struct x86_emulate_ctxt *ctxt)
 {
 	long sv = 0, mask;
 
-	if (c->dst.type == OP_MEM && c->src.type == OP_REG) {
-		mask = ~(c->dst.bytes * 8 - 1);
+	if (ctxt->dst.type == OP_MEM && ctxt->src.type == OP_REG) {
+		mask = ~(ctxt->dst.bytes * 8 - 1);
 
-		if (c->src.bytes == 2)
-			sv = (s16)c->src.val & (s16)mask;
-		else if (c->src.bytes == 4)
-			sv = (s32)c->src.val & (s32)mask;
+		if (ctxt->src.bytes == 2)
+			sv = (s16)ctxt->src.val & (s16)mask;
+		else if (ctxt->src.bytes == 4)
+			sv = (s32)ctxt->src.val & (s32)mask;
 
-		c->dst.addr.mem.ea += (sv >> 3);
+		ctxt->dst.addr.mem.ea += (sv >> 3);
 	}
 
 	/* only subword offset */
-	c->src.val &= (c->dst.bytes << 3) - 1;
+	ctxt->src.val &= (ctxt->dst.bytes << 3) - 1;
 }
 
 static int read_emulated(struct x86_emulate_ctxt *ctxt,
-			 struct x86_emulate_ops *ops,
 			 unsigned long addr, void *dest, unsigned size)
 {
 	int rc;
-	struct read_cache *mc = &ctxt->decode.mem_read;
+	struct read_cache *mc = &ctxt->mem_read;
 
 	while (size) {
 		int n = min(size, 8u);
@@ -1068,8 +1057,8 @@ static int read_emulated(struct x86_emulate_ctxt *ctxt,
 		if (mc->pos < mc->end)
 			goto read_cached;
 
-		rc = ops->read_emulated(ctxt, addr, mc->data + mc->end, n,
-					&ctxt->exception);
+		rc = ctxt->ops->read_emulated(ctxt, addr, mc->data + mc->end, n,
+					      &ctxt->exception);
 		if (rc != X86EMUL_CONTINUE)
 			return rc;
 		mc->end += n;
@@ -1094,7 +1083,7 @@ static int segmented_read(struct x86_emulate_ctxt *ctxt,
 	rc = linearize(ctxt, addr, size, false, &linear);
 	if (rc != X86EMUL_CONTINUE)
 		return rc;
-	return read_emulated(ctxt, ctxt->ops, linear, data, size);
+	return read_emulated(ctxt, linear, data, size);
 }
 
 static int segmented_write(struct x86_emulate_ctxt *ctxt,
@@ -1128,26 +1117,24 @@ static int segmented_cmpxchg(struct x86_emulate_ctxt *ctxt,
 }
 
 static int pio_in_emulated(struct x86_emulate_ctxt *ctxt,
-			   struct x86_emulate_ops *ops,
 			   unsigned int size, unsigned short port,
 			   void *dest)
 {
-	struct read_cache *rc = &ctxt->decode.io_read;
+	struct read_cache *rc = &ctxt->io_read;
 
 	if (rc->pos == rc->end) { /* refill pio read ahead */
-		struct decode_cache *c = &ctxt->decode;
 		unsigned int in_page, n;
-		unsigned int count = c->rep_prefix ?
-			address_mask(c, c->regs[VCPU_REGS_RCX]) : 1;
+		unsigned int count = ctxt->rep_prefix ?
+			address_mask(ctxt, ctxt->regs[VCPU_REGS_RCX]) : 1;
 		in_page = (ctxt->eflags & EFLG_DF) ?
-			offset_in_page(c->regs[VCPU_REGS_RDI]) :
-			PAGE_SIZE - offset_in_page(c->regs[VCPU_REGS_RDI]);
+			offset_in_page(ctxt->regs[VCPU_REGS_RDI]) :
+			PAGE_SIZE - offset_in_page(ctxt->regs[VCPU_REGS_RDI]);
 		n = min(min(in_page, (unsigned int)sizeof(rc->data)) / size,
 			count);
 		if (n == 0)
 			n = 1;
 		rc->pos = rc->end = 0;
-		if (!ops->pio_in_emulated(ctxt, size, port, rc->data, n))
+		if (!ctxt->ops->pio_in_emulated(ctxt, size, port, rc->data, n))
 			return 0;
 		rc->end = n * size;
 	}
@@ -1158,9 +1145,10 @@ static int pio_in_emulated(struct x86_emulate_ctxt *ctxt,
 }
 
 static void get_descriptor_table_ptr(struct x86_emulate_ctxt *ctxt,
-				     struct x86_emulate_ops *ops,
 				     u16 selector, struct desc_ptr *dt)
 {
+	struct x86_emulate_ops *ops = ctxt->ops;
+
 	if (selector & 1 << 2) {
 		struct desc_struct desc;
 		u16 sel;
@@ -1177,48 +1165,42 @@ static void get_descriptor_table_ptr(struct x86_emulate_ctxt *ctxt,
 
 /* allowed just for 8 bytes segments */
 static int read_segment_descriptor(struct x86_emulate_ctxt *ctxt,
-				   struct x86_emulate_ops *ops,
 				   u16 selector, struct desc_struct *desc)
 {
 	struct desc_ptr dt;
 	u16 index = selector >> 3;
-	int ret;
 	ulong addr;
 
-	get_descriptor_table_ptr(ctxt, ops, selector, &dt);
+	get_descriptor_table_ptr(ctxt, selector, &dt);
 
 	if (dt.size < index * 8 + 7)
 		return emulate_gp(ctxt, selector & 0xfffc);
-	addr = dt.address + index * 8;
-	ret = ops->read_std(ctxt, addr, desc, sizeof *desc, &ctxt->exception);
 
-       return ret;
+	addr = dt.address + index * 8;
+	return ctxt->ops->read_std(ctxt, addr, desc, sizeof *desc,
+				   &ctxt->exception);
 }
 
 /* allowed just for 8 bytes segments */
 static int write_segment_descriptor(struct x86_emulate_ctxt *ctxt,
-				    struct x86_emulate_ops *ops,
 				    u16 selector, struct desc_struct *desc)
 {
 	struct desc_ptr dt;
 	u16 index = selector >> 3;
 	ulong addr;
-	int ret;
 
-	get_descriptor_table_ptr(ctxt, ops, selector, &dt);
+	get_descriptor_table_ptr(ctxt, selector, &dt);
 
 	if (dt.size < index * 8 + 7)
 		return emulate_gp(ctxt, selector & 0xfffc);
 
 	addr = dt.address + index * 8;
-	ret = ops->write_std(ctxt, addr, desc, sizeof *desc, &ctxt->exception);
-
-	return ret;
+	return ctxt->ops->write_std(ctxt, addr, desc, sizeof *desc,
+				    &ctxt->exception);
 }
 
 /* Does not support long mode */
 static int load_segment_descriptor(struct x86_emulate_ctxt *ctxt,
-				   struct x86_emulate_ops *ops,
 				   u16 selector, int seg)
 {
 	struct desc_struct seg_desc;
@@ -1253,7 +1235,7 @@ static int load_segment_descriptor(struct x86_emulate_ctxt *ctxt,
 	if (null_selector) /* for NULL selector skip all following checks */
 		goto load;
 
-	ret = read_segment_descriptor(ctxt, ops, selector, &seg_desc);
+	ret = read_segment_descriptor(ctxt, selector, &seg_desc);
 	if (ret != X86EMUL_CONTINUE)
 		return ret;
 
@@ -1271,7 +1253,7 @@ static int load_segment_descriptor(struct x86_emulate_ctxt *ctxt,
 
 	rpl = selector & 3;
 	dpl = seg_desc.dpl;
-	cpl = ops->cpl(ctxt);
+	cpl = ctxt->ops->cpl(ctxt);
 
 	switch (seg) {
 	case VCPU_SREG_SS:
@@ -1322,12 +1304,12 @@ static int load_segment_descriptor(struct x86_emulate_ctxt *ctxt,
 	if (seg_desc.s) {
 		/* mark segment as accessed */
 		seg_desc.type |= 1;
-		ret = write_segment_descriptor(ctxt, ops, selector, &seg_desc);
+		ret = write_segment_descriptor(ctxt, selector, &seg_desc);
 		if (ret != X86EMUL_CONTINUE)
 			return ret;
 	}
 load:
-	ops->set_segment(ctxt, selector, &seg_desc, 0, seg);
+	ctxt->ops->set_segment(ctxt, selector, &seg_desc, 0, seg);
 	return X86EMUL_CONTINUE;
 exception:
 	emulate_exception(ctxt, err_vec, err_code, true);
@@ -1356,29 +1338,28 @@ static void write_register_operand(struct operand *op)
 static int writeback(struct x86_emulate_ctxt *ctxt)
 {
 	int rc;
-	struct decode_cache *c = &ctxt->decode;
 
-	switch (c->dst.type) {
+	switch (ctxt->dst.type) {
 	case OP_REG:
-		write_register_operand(&c->dst);
+		write_register_operand(&ctxt->dst);
 		break;
 	case OP_MEM:
-		if (c->lock_prefix)
+		if (ctxt->lock_prefix)
 			rc = segmented_cmpxchg(ctxt,
-					       c->dst.addr.mem,
-					       &c->dst.orig_val,
-					       &c->dst.val,
-					       c->dst.bytes);
+					       ctxt->dst.addr.mem,
+					       &ctxt->dst.orig_val,
+					       &ctxt->dst.val,
+					       ctxt->dst.bytes);
 		else
 			rc = segmented_write(ctxt,
-					     c->dst.addr.mem,
-					     &c->dst.val,
-					     c->dst.bytes);
+					     ctxt->dst.addr.mem,
+					     &ctxt->dst.val,
+					     ctxt->dst.bytes);
 		if (rc != X86EMUL_CONTINUE)
 			return rc;
 		break;
 	case OP_XMM:
-		write_sse_reg(ctxt, &c->dst.vec_val, c->dst.addr.xmm);
+		write_sse_reg(ctxt, &ctxt->dst.vec_val, ctxt->dst.addr.xmm);
 		break;
 	case OP_NONE:
 		/* no writeback */
@@ -1391,50 +1372,45 @@ static int writeback(struct x86_emulate_ctxt *ctxt)
 
 static int em_push(struct x86_emulate_ctxt *ctxt)
 {
-	struct decode_cache *c = &ctxt->decode;
 	struct segmented_address addr;
 
-	register_address_increment(c, &c->regs[VCPU_REGS_RSP], -c->op_bytes);
-	addr.ea = register_address(c, c->regs[VCPU_REGS_RSP]);
+	register_address_increment(ctxt, &ctxt->regs[VCPU_REGS_RSP], -ctxt->op_bytes);
+	addr.ea = register_address(ctxt, ctxt->regs[VCPU_REGS_RSP]);
 	addr.seg = VCPU_SREG_SS;
 
 	/* Disable writeback. */
-	c->dst.type = OP_NONE;
-	return segmented_write(ctxt, addr, &c->src.val, c->op_bytes);
+	ctxt->dst.type = OP_NONE;
+	return segmented_write(ctxt, addr, &ctxt->src.val, ctxt->op_bytes);
 }
 
 static int emulate_pop(struct x86_emulate_ctxt *ctxt,
 		       void *dest, int len)
 {
-	struct decode_cache *c = &ctxt->decode;
 	int rc;
 	struct segmented_address addr;
 
-	addr.ea = register_address(c, c->regs[VCPU_REGS_RSP]);
+	addr.ea = register_address(ctxt, ctxt->regs[VCPU_REGS_RSP]);
 	addr.seg = VCPU_SREG_SS;
 	rc = segmented_read(ctxt, addr, dest, len);
 	if (rc != X86EMUL_CONTINUE)
 		return rc;
 
-	register_address_increment(c, &c->regs[VCPU_REGS_RSP], len);
+	register_address_increment(ctxt, &ctxt->regs[VCPU_REGS_RSP], len);
 	return rc;
 }
 
 static int em_pop(struct x86_emulate_ctxt *ctxt)
 {
-	struct decode_cache *c = &ctxt->decode;
-
-	return emulate_pop(ctxt, &c->dst.val, c->op_bytes);
+	return emulate_pop(ctxt, &ctxt->dst.val, ctxt->op_bytes);
 }
 
 static int emulate_popf(struct x86_emulate_ctxt *ctxt,
-		       struct x86_emulate_ops *ops,
-		       void *dest, int len)
+			void *dest, int len)
 {
 	int rc;
 	unsigned long val, change_mask;
 	int iopl = (ctxt->eflags & X86_EFLAGS_IOPL) >> IOPL_SHIFT;
-	int cpl = ops->cpl(ctxt);
+	int cpl = ctxt->ops->cpl(ctxt);
 
 	rc = emulate_pop(ctxt, &val, len);
 	if (rc != X86EMUL_CONTINUE)
@@ -1470,49 +1446,41 @@ static int emulate_popf(struct x86_emulate_ctxt *ctxt,
 
 static int em_popf(struct x86_emulate_ctxt *ctxt)
 {
-	struct decode_cache *c = &ctxt->decode;
-
-	c->dst.type = OP_REG;
-	c->dst.addr.reg = &ctxt->eflags;
-	c->dst.bytes = c->op_bytes;
-	return emulate_popf(ctxt, ctxt->ops, &c->dst.val, c->op_bytes);
+	ctxt->dst.type = OP_REG;
+	ctxt->dst.addr.reg = &ctxt->eflags;
+	ctxt->dst.bytes = ctxt->op_bytes;
+	return emulate_popf(ctxt, &ctxt->dst.val, ctxt->op_bytes);
 }
 
-static int emulate_push_sreg(struct x86_emulate_ctxt *ctxt,
-			     struct x86_emulate_ops *ops, int seg)
+static int emulate_push_sreg(struct x86_emulate_ctxt *ctxt, int seg)
 {
-	struct decode_cache *c = &ctxt->decode;
-
-	c->src.val = get_segment_selector(ctxt, seg);
+	ctxt->src.val = get_segment_selector(ctxt, seg);
 
 	return em_push(ctxt);
 }
 
-static int emulate_pop_sreg(struct x86_emulate_ctxt *ctxt,
-			     struct x86_emulate_ops *ops, int seg)
+static int emulate_pop_sreg(struct x86_emulate_ctxt *ctxt, int seg)
 {
-	struct decode_cache *c = &ctxt->decode;
 	unsigned long selector;
 	int rc;
 
-	rc = emulate_pop(ctxt, &selector, c->op_bytes);
+	rc = emulate_pop(ctxt, &selector, ctxt->op_bytes);
 	if (rc != X86EMUL_CONTINUE)
 		return rc;
 
-	rc = load_segment_descriptor(ctxt, ops, (u16)selector, seg);
+	rc = load_segment_descriptor(ctxt, (u16)selector, seg);
 	return rc;
 }
 
 static int em_pusha(struct x86_emulate_ctxt *ctxt)
 {
-	struct decode_cache *c = &ctxt->decode;
-	unsigned long old_esp = c->regs[VCPU_REGS_RSP];
+	unsigned long old_esp = ctxt->regs[VCPU_REGS_RSP];
 	int rc = X86EMUL_CONTINUE;
 	int reg = VCPU_REGS_RAX;
 
 	while (reg <= VCPU_REGS_RDI) {
 		(reg == VCPU_REGS_RSP) ?
-		(c->src.val = old_esp) : (c->src.val = c->regs[reg]);
+		(ctxt->src.val = old_esp) : (ctxt->src.val = ctxt->regs[reg]);
 
 		rc = em_push(ctxt);
 		if (rc != X86EMUL_CONTINUE)
@@ -1526,26 +1494,23 @@ static int em_pusha(struct x86_emulate_ctxt *ctxt)
 
 static int em_pushf(struct x86_emulate_ctxt *ctxt)
 {
-	struct decode_cache *c = &ctxt->decode;
-
-	c->src.val =  (unsigned long)ctxt->eflags;
+	ctxt->src.val =  (unsigned long)ctxt->eflags;
 	return em_push(ctxt);
 }
 
 static int em_popa(struct x86_emulate_ctxt *ctxt)
 {
-	struct decode_cache *c = &ctxt->decode;
 	int rc = X86EMUL_CONTINUE;
 	int reg = VCPU_REGS_RDI;
 
 	while (reg >= VCPU_REGS_RAX) {
 		if (reg == VCPU_REGS_RSP) {
-			register_address_increment(c, &c->regs[VCPU_REGS_RSP],
-							c->op_bytes);
+			register_address_increment(ctxt, &ctxt->regs[VCPU_REGS_RSP],
+							ctxt->op_bytes);
 			--reg;
 		}
 
-		rc = emulate_pop(ctxt, &c->regs[reg], c->op_bytes);
+		rc = emulate_pop(ctxt, &ctxt->regs[reg], ctxt->op_bytes);
 		if (rc != X86EMUL_CONTINUE)
 			break;
 		--reg;
@@ -1553,10 +1518,9 @@ static int em_popa(struct x86_emulate_ctxt *ctxt)
 	return rc;
 }
 
-int emulate_int_real(struct x86_emulate_ctxt *ctxt,
-			       struct x86_emulate_ops *ops, int irq)
+int emulate_int_real(struct x86_emulate_ctxt *ctxt, int irq)
 {
-	struct decode_cache *c = &ctxt->decode;
+	struct x86_emulate_ops *ops = ctxt->ops;
 	int rc;
 	struct desc_ptr dt;
 	gva_t cs_addr;
@@ -1564,19 +1528,19 @@ int emulate_int_real(struct x86_emulate_ctxt *ctxt,
 	u16 cs, eip;
 
 	/* TODO: Add limit checks */
-	c->src.val = ctxt->eflags;
+	ctxt->src.val = ctxt->eflags;
 	rc = em_push(ctxt);
 	if (rc != X86EMUL_CONTINUE)
 		return rc;
 
 	ctxt->eflags &= ~(EFLG_IF | EFLG_TF | EFLG_AC);
 
-	c->src.val = get_segment_selector(ctxt, VCPU_SREG_CS);
+	ctxt->src.val = get_segment_selector(ctxt, VCPU_SREG_CS);
 	rc = em_push(ctxt);
 	if (rc != X86EMUL_CONTINUE)
 		return rc;
 
-	c->src.val = c->eip;
+	ctxt->src.val = ctxt->_eip;
 	rc = em_push(ctxt);
 	if (rc != X86EMUL_CONTINUE)
 		return rc;
@@ -1594,21 +1558,20 @@ int emulate_int_real(struct x86_emulate_ctxt *ctxt,
 	if (rc != X86EMUL_CONTINUE)
 		return rc;
 
-	rc = load_segment_descriptor(ctxt, ops, cs, VCPU_SREG_CS);
+	rc = load_segment_descriptor(ctxt, cs, VCPU_SREG_CS);
 	if (rc != X86EMUL_CONTINUE)
 		return rc;
 
-	c->eip = eip;
+	ctxt->_eip = eip;
 
 	return rc;
 }
 
-static int emulate_int(struct x86_emulate_ctxt *ctxt,
-		       struct x86_emulate_ops *ops, int irq)
+static int emulate_int(struct x86_emulate_ctxt *ctxt, int irq)
 {
 	switch(ctxt->mode) {
 	case X86EMUL_MODE_REAL:
-		return emulate_int_real(ctxt, ops, irq);
+		return emulate_int_real(ctxt, irq);
 	case X86EMUL_MODE_VM86:
 	case X86EMUL_MODE_PROT16:
 	case X86EMUL_MODE_PROT32:
@@ -1619,10 +1582,8 @@ static int emulate_int(struct x86_emulate_ctxt *ctxt,
 	}
 }
 
-static int emulate_iret_real(struct x86_emulate_ctxt *ctxt,
-			     struct x86_emulate_ops *ops)
+static int emulate_iret_real(struct x86_emulate_ctxt *ctxt)
 {
-	struct decode_cache *c = &ctxt->decode;
 	int rc = X86EMUL_CONTINUE;
 	unsigned long temp_eip = 0;
 	unsigned long temp_eflags = 0;
@@ -1634,7 +1595,7 @@ static int emulate_iret_real(struct x86_emulate_ctxt *ctxt,
 
 	/* TODO: Add stack limit check */
 
-	rc = emulate_pop(ctxt, &temp_eip, c->op_bytes);
+	rc = emulate_pop(ctxt, &temp_eip, ctxt->op_bytes);
 
 	if (rc != X86EMUL_CONTINUE)
 		return rc;
@@ -1642,27 +1603,27 @@ static int emulate_iret_real(struct x86_emulate_ctxt *ctxt,
 	if (temp_eip & ~0xffff)
 		return emulate_gp(ctxt, 0);
 
-	rc = emulate_pop(ctxt, &cs, c->op_bytes);
+	rc = emulate_pop(ctxt, &cs, ctxt->op_bytes);
 
 	if (rc != X86EMUL_CONTINUE)
 		return rc;
 
-	rc = emulate_pop(ctxt, &temp_eflags, c->op_bytes);
+	rc = emulate_pop(ctxt, &temp_eflags, ctxt->op_bytes);
 
 	if (rc != X86EMUL_CONTINUE)
 		return rc;
 
-	rc = load_segment_descriptor(ctxt, ops, (u16)cs, VCPU_SREG_CS);
+	rc = load_segment_descriptor(ctxt, (u16)cs, VCPU_SREG_CS);
 
 	if (rc != X86EMUL_CONTINUE)
 		return rc;
 
-	c->eip = temp_eip;
+	ctxt->_eip = temp_eip;
 
 
-	if (c->op_bytes == 4)
+	if (ctxt->op_bytes == 4)
 		ctxt->eflags = ((temp_eflags & mask) | (ctxt->eflags & vm86_mask));
-	else if (c->op_bytes == 2) {
+	else if (ctxt->op_bytes == 2) {
 		ctxt->eflags &= ~0xffff;
 		ctxt->eflags |= temp_eflags;
 	}
@@ -1673,12 +1634,11 @@ static int emulate_iret_real(struct x86_emulate_ctxt *ctxt,
 	return rc;
 }
 
-static inline int emulate_iret(struct x86_emulate_ctxt *ctxt,
-				    struct x86_emulate_ops* ops)
+static int em_iret(struct x86_emulate_ctxt *ctxt)
 {
 	switch(ctxt->mode) {
 	case X86EMUL_MODE_REAL:
-		return emulate_iret_real(ctxt, ops);
+		return emulate_iret_real(ctxt);
 	case X86EMUL_MODE_VM86:
 	case X86EMUL_MODE_PROT16:
 	case X86EMUL_MODE_PROT32:
@@ -1691,53 +1651,49 @@ static inline int emulate_iret(struct x86_emulate_ctxt *ctxt,
 
 static int em_jmp_far(struct x86_emulate_ctxt *ctxt)
 {
-	struct decode_cache *c = &ctxt->decode;
 	int rc;
 	unsigned short sel;
 
-	memcpy(&sel, c->src.valptr + c->op_bytes, 2);
+	memcpy(&sel, ctxt->src.valptr + ctxt->op_bytes, 2);
 
-	rc = load_segment_descriptor(ctxt, ctxt->ops, sel, VCPU_SREG_CS);
+	rc = load_segment_descriptor(ctxt, sel, VCPU_SREG_CS);
 	if (rc != X86EMUL_CONTINUE)
 		return rc;
 
-	c->eip = 0;
-	memcpy(&c->eip, c->src.valptr, c->op_bytes);
+	ctxt->_eip = 0;
+	memcpy(&ctxt->_eip, ctxt->src.valptr, ctxt->op_bytes);
 	return X86EMUL_CONTINUE;
 }
 
 static int em_grp1a(struct x86_emulate_ctxt *ctxt)
 {
-	struct decode_cache *c = &ctxt->decode;
-
-	return emulate_pop(ctxt, &c->dst.val, c->dst.bytes);
+	return emulate_pop(ctxt, &ctxt->dst.val, ctxt->dst.bytes);
 }
 
 static int em_grp2(struct x86_emulate_ctxt *ctxt)
 {
-	struct decode_cache *c = &ctxt->decode;
-	switch (c->modrm_reg) {
+	switch (ctxt->modrm_reg) {
 	case 0:	/* rol */
-		emulate_2op_SrcB("rol", c->src, c->dst, ctxt->eflags);
+		emulate_2op_SrcB("rol", ctxt->src, ctxt->dst, ctxt->eflags);
 		break;
 	case 1:	/* ror */
-		emulate_2op_SrcB("ror", c->src, c->dst, ctxt->eflags);
+		emulate_2op_SrcB("ror", ctxt->src, ctxt->dst, ctxt->eflags);
 		break;
 	case 2:	/* rcl */
-		emulate_2op_SrcB("rcl", c->src, c->dst, ctxt->eflags);
+		emulate_2op_SrcB("rcl", ctxt->src, ctxt->dst, ctxt->eflags);
 		break;
 	case 3:	/* rcr */
-		emulate_2op_SrcB("rcr", c->src, c->dst, ctxt->eflags);
+		emulate_2op_SrcB("rcr", ctxt->src, ctxt->dst, ctxt->eflags);
 		break;
 	case 4:	/* sal/shl */
 	case 6:	/* sal/shl */
-		emulate_2op_SrcB("sal", c->src, c->dst, ctxt->eflags);
+		emulate_2op_SrcB("sal", ctxt->src, ctxt->dst, ctxt->eflags);
 		break;
 	case 5:	/* shr */
-		emulate_2op_SrcB("shr", c->src, c->dst, ctxt->eflags);
+		emulate_2op_SrcB("shr", ctxt->src, ctxt->dst, ctxt->eflags);
 		break;
 	case 7:	/* sar */
-		emulate_2op_SrcB("sar", c->src, c->dst, ctxt->eflags);
+		emulate_2op_SrcB("sar", ctxt->src, ctxt->dst, ctxt->eflags);
 		break;
 	}
 	return X86EMUL_CONTINUE;
@@ -1745,33 +1701,32 @@ static int em_grp2(struct x86_emulate_ctxt *ctxt)
 
 static int em_grp3(struct x86_emulate_ctxt *ctxt)
 {
-	struct decode_cache *c = &ctxt->decode;
-	unsigned long *rax = &c->regs[VCPU_REGS_RAX];
-	unsigned long *rdx = &c->regs[VCPU_REGS_RDX];
+	unsigned long *rax = &ctxt->regs[VCPU_REGS_RAX];
+	unsigned long *rdx = &ctxt->regs[VCPU_REGS_RDX];
 	u8 de = 0;
 
-	switch (c->modrm_reg) {
+	switch (ctxt->modrm_reg) {
 	case 0 ... 1:	/* test */
-		emulate_2op_SrcV("test", c->src, c->dst, ctxt->eflags);
+		emulate_2op_SrcV("test", ctxt->src, ctxt->dst, ctxt->eflags);
 		break;
 	case 2:	/* not */
-		c->dst.val = ~c->dst.val;
+		ctxt->dst.val = ~ctxt->dst.val;
 		break;
 	case 3:	/* neg */
-		emulate_1op("neg", c->dst, ctxt->eflags);
+		emulate_1op("neg", ctxt->dst, ctxt->eflags);
 		break;
 	case 4: /* mul */
-		emulate_1op_rax_rdx("mul", c->src, *rax, *rdx, ctxt->eflags);
+		emulate_1op_rax_rdx("mul", ctxt->src, *rax, *rdx, ctxt->eflags);
 		break;
 	case 5: /* imul */
-		emulate_1op_rax_rdx("imul", c->src, *rax, *rdx, ctxt->eflags);
+		emulate_1op_rax_rdx("imul", ctxt->src, *rax, *rdx, ctxt->eflags);
 		break;
 	case 6: /* div */
-		emulate_1op_rax_rdx_ex("div", c->src, *rax, *rdx,
+		emulate_1op_rax_rdx_ex("div", ctxt->src, *rax, *rdx,
 				       ctxt->eflags, de);
 		break;
 	case 7: /* idiv */
-		emulate_1op_rax_rdx_ex("idiv", c->src, *rax, *rdx,
+		emulate_1op_rax_rdx_ex("idiv", ctxt->src, *rax, *rdx,
 				       ctxt->eflags, de);
 		break;
 	default:
@@ -1784,26 +1739,25 @@ static int em_grp3(struct x86_emulate_ctxt *ctxt)
 
 static int em_grp45(struct x86_emulate_ctxt *ctxt)
 {
-	struct decode_cache *c = &ctxt->decode;
 	int rc = X86EMUL_CONTINUE;
 
-	switch (c->modrm_reg) {
+	switch (ctxt->modrm_reg) {
 	case 0:	/* inc */
-		emulate_1op("inc", c->dst, ctxt->eflags);
+		emulate_1op("inc", ctxt->dst, ctxt->eflags);
 		break;
 	case 1:	/* dec */
-		emulate_1op("dec", c->dst, ctxt->eflags);
+		emulate_1op("dec", ctxt->dst, ctxt->eflags);
 		break;
 	case 2: /* call near abs */ {
 		long int old_eip;
-		old_eip = c->eip;
-		c->eip = c->src.val;
-		c->src.val = old_eip;
+		old_eip = ctxt->_eip;
+		ctxt->_eip = ctxt->src.val;
+		ctxt->src.val = old_eip;
 		rc = em_push(ctxt);
 		break;
 	}
 	case 4: /* jmp abs */
-		c->eip = c->src.val;
+		ctxt->_eip = ctxt->src.val;
 		break;
 	case 5: /* jmp far */
 		rc = em_jmp_far(ctxt);
@@ -1817,68 +1771,70 @@ static int em_grp45(struct x86_emulate_ctxt *ctxt)
 
 static int em_grp9(struct x86_emulate_ctxt *ctxt)
 {
-	struct decode_cache *c = &ctxt->decode;
-	u64 old = c->dst.orig_val64;
+	u64 old = ctxt->dst.orig_val64;
 
-	if (((u32) (old >> 0) != (u32) c->regs[VCPU_REGS_RAX]) ||
-	    ((u32) (old >> 32) != (u32) c->regs[VCPU_REGS_RDX])) {
-		c->regs[VCPU_REGS_RAX] = (u32) (old >> 0);
-		c->regs[VCPU_REGS_RDX] = (u32) (old >> 32);
+	if (((u32) (old >> 0) != (u32) ctxt->regs[VCPU_REGS_RAX]) ||
+	    ((u32) (old >> 32) != (u32) ctxt->regs[VCPU_REGS_RDX])) {
+		ctxt->regs[VCPU_REGS_RAX] = (u32) (old >> 0);
+		ctxt->regs[VCPU_REGS_RDX] = (u32) (old >> 32);
 		ctxt->eflags &= ~EFLG_ZF;
 	} else {
-		c->dst.val64 = ((u64)c->regs[VCPU_REGS_RCX] << 32) |
-			(u32) c->regs[VCPU_REGS_RBX];
+		ctxt->dst.val64 = ((u64)ctxt->regs[VCPU_REGS_RCX] << 32) |
+			(u32) ctxt->regs[VCPU_REGS_RBX];
 
 		ctxt->eflags |= EFLG_ZF;
 	}
 	return X86EMUL_CONTINUE;
 }
 
-static int emulate_ret_far(struct x86_emulate_ctxt *ctxt,
-			   struct x86_emulate_ops *ops)
+static int em_ret(struct x86_emulate_ctxt *ctxt)
+{
+	ctxt->dst.type = OP_REG;
+	ctxt->dst.addr.reg = &ctxt->_eip;
+	ctxt->dst.bytes = ctxt->op_bytes;
+	return em_pop(ctxt);
+}
+
+static int em_ret_far(struct x86_emulate_ctxt *ctxt)
 {
-	struct decode_cache *c = &ctxt->decode;
 	int rc;
 	unsigned long cs;
 
-	rc = emulate_pop(ctxt, &c->eip, c->op_bytes);
+	rc = emulate_pop(ctxt, &ctxt->_eip, ctxt->op_bytes);
 	if (rc != X86EMUL_CONTINUE)
 		return rc;
-	if (c->op_bytes == 4)
-		c->eip = (u32)c->eip;
-	rc = emulate_pop(ctxt, &cs, c->op_bytes);
+	if (ctxt->op_bytes == 4)
+		ctxt->_eip = (u32)ctxt->_eip;
+	rc = emulate_pop(ctxt, &cs, ctxt->op_bytes);
 	if (rc != X86EMUL_CONTINUE)
 		return rc;
-	rc = load_segment_descriptor(ctxt, ops, (u16)cs, VCPU_SREG_CS);
+	rc = load_segment_descriptor(ctxt, (u16)cs, VCPU_SREG_CS);
 	return rc;
 }
 
-static int emulate_load_segment(struct x86_emulate_ctxt *ctxt,
-			   struct x86_emulate_ops *ops, int seg)
+static int emulate_load_segment(struct x86_emulate_ctxt *ctxt, int seg)
 {
-	struct decode_cache *c = &ctxt->decode;
 	unsigned short sel;
 	int rc;
 
-	memcpy(&sel, c->src.valptr + c->op_bytes, 2);
+	memcpy(&sel, ctxt->src.valptr + ctxt->op_bytes, 2);
 
-	rc = load_segment_descriptor(ctxt, ops, sel, seg);
+	rc = load_segment_descriptor(ctxt, sel, seg);
 	if (rc != X86EMUL_CONTINUE)
 		return rc;
 
-	c->dst.val = c->src.val;
+	ctxt->dst.val = ctxt->src.val;
 	return rc;
 }
 
-static inline void
+static void
 setup_syscalls_segments(struct x86_emulate_ctxt *ctxt,
-			struct x86_emulate_ops *ops, struct desc_struct *cs,
-			struct desc_struct *ss)
+			struct desc_struct *cs, struct desc_struct *ss)
 {
 	u16 selector;
 
 	memset(cs, 0, sizeof(struct desc_struct));
-	ops->get_segment(ctxt, &selector, cs, NULL, VCPU_SREG_CS);
+	ctxt->ops->get_segment(ctxt, &selector, cs, NULL, VCPU_SREG_CS);
 	memset(ss, 0, sizeof(struct desc_struct));
 
 	cs->l = 0;		/* will be adjusted later */
@@ -1901,10 +1857,9 @@ setup_syscalls_segments(struct x86_emulate_ctxt *ctxt,
 	ss->p = 1;
 }
 
-static int
-emulate_syscall(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops)
+static int em_syscall(struct x86_emulate_ctxt *ctxt)
 {
-	struct decode_cache *c = &ctxt->decode;
+	struct x86_emulate_ops *ops = ctxt->ops;
 	struct desc_struct cs, ss;
 	u64 msr_data;
 	u16 cs_sel, ss_sel;
@@ -1916,7 +1871,7 @@ emulate_syscall(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops)
 		return emulate_ud(ctxt);
 
 	ops->get_msr(ctxt, MSR_EFER, &efer);
-	setup_syscalls_segments(ctxt, ops, &cs, &ss);
+	setup_syscalls_segments(ctxt, &cs, &ss);
 
 	ops->get_msr(ctxt, MSR_STAR, &msr_data);
 	msr_data >>= 32;
@@ -1930,15 +1885,15 @@ emulate_syscall(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops)
 	ops->set_segment(ctxt, cs_sel, &cs, 0, VCPU_SREG_CS);
 	ops->set_segment(ctxt, ss_sel, &ss, 0, VCPU_SREG_SS);
 
-	c->regs[VCPU_REGS_RCX] = c->eip;
+	ctxt->regs[VCPU_REGS_RCX] = ctxt->_eip;
 	if (efer & EFER_LMA) {
 #ifdef CONFIG_X86_64
-		c->regs[VCPU_REGS_R11] = ctxt->eflags & ~EFLG_RF;
+		ctxt->regs[VCPU_REGS_R11] = ctxt->eflags & ~EFLG_RF;
 
 		ops->get_msr(ctxt,
 			     ctxt->mode == X86EMUL_MODE_PROT64 ?
 			     MSR_LSTAR : MSR_CSTAR, &msr_data);
-		c->eip = msr_data;
+		ctxt->_eip = msr_data;
 
 		ops->get_msr(ctxt, MSR_SYSCALL_MASK, &msr_data);
 		ctxt->eflags &= ~(msr_data | EFLG_RF);
@@ -1946,7 +1901,7 @@ emulate_syscall(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops)
 	} else {
 		/* legacy mode */
 		ops->get_msr(ctxt, MSR_STAR, &msr_data);
-		c->eip = (u32)msr_data;
+		ctxt->_eip = (u32)msr_data;
 
 		ctxt->eflags &= ~(EFLG_VM | EFLG_IF | EFLG_RF);
 	}
@@ -1954,16 +1909,15 @@ emulate_syscall(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops)
 	return X86EMUL_CONTINUE;
 }
 
-static int
-emulate_sysenter(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops)
+static int em_sysenter(struct x86_emulate_ctxt *ctxt)
 {
-	struct decode_cache *c = &ctxt->decode;
+	struct x86_emulate_ops *ops = ctxt->ops;
 	struct desc_struct cs, ss;
 	u64 msr_data;
 	u16 cs_sel, ss_sel;
 	u64 efer = 0;
 
-	ctxt->ops->get_msr(ctxt, MSR_EFER, &efer);
+	ops->get_msr(ctxt, MSR_EFER, &efer);
 	/* inject #GP if in real mode */
 	if (ctxt->mode == X86EMUL_MODE_REAL)
 		return emulate_gp(ctxt, 0);
@@ -1974,7 +1928,7 @@ emulate_sysenter(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops)
 	if (ctxt->mode == X86EMUL_MODE_PROT64)
 		return emulate_ud(ctxt);
 
-	setup_syscalls_segments(ctxt, ops, &cs, &ss);
+	setup_syscalls_segments(ctxt, &cs, &ss);
 
 	ops->get_msr(ctxt, MSR_IA32_SYSENTER_CS, &msr_data);
 	switch (ctxt->mode) {
@@ -2002,31 +1956,30 @@ emulate_sysenter(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops)
 	ops->set_segment(ctxt, ss_sel, &ss, 0, VCPU_SREG_SS);
 
 	ops->get_msr(ctxt, MSR_IA32_SYSENTER_EIP, &msr_data);
-	c->eip = msr_data;
+	ctxt->_eip = msr_data;
 
 	ops->get_msr(ctxt, MSR_IA32_SYSENTER_ESP, &msr_data);
-	c->regs[VCPU_REGS_RSP] = msr_data;
+	ctxt->regs[VCPU_REGS_RSP] = msr_data;
 
 	return X86EMUL_CONTINUE;
 }
 
-static int
-emulate_sysexit(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops)
+static int em_sysexit(struct x86_emulate_ctxt *ctxt)
 {
-	struct decode_cache *c = &ctxt->decode;
+	struct x86_emulate_ops *ops = ctxt->ops;
 	struct desc_struct cs, ss;
 	u64 msr_data;
 	int usermode;
-	u16 cs_sel, ss_sel;
+	u16 cs_sel = 0, ss_sel = 0;
 
 	/* inject #GP if in real mode or Virtual 8086 mode */
 	if (ctxt->mode == X86EMUL_MODE_REAL ||
 	    ctxt->mode == X86EMUL_MODE_VM86)
 		return emulate_gp(ctxt, 0);
 
-	setup_syscalls_segments(ctxt, ops, &cs, &ss);
+	setup_syscalls_segments(ctxt, &cs, &ss);
 
-	if ((c->rex_prefix & 0x8) != 0x0)
+	if ((ctxt->rex_prefix & 0x8) != 0x0)
 		usermode = X86EMUL_MODE_PROT64;
 	else
 		usermode = X86EMUL_MODE_PROT32;
@@ -2056,14 +2009,13 @@ emulate_sysexit(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops)
 	ops->set_segment(ctxt, cs_sel, &cs, 0, VCPU_SREG_CS);
 	ops->set_segment(ctxt, ss_sel, &ss, 0, VCPU_SREG_SS);
 
-	c->eip = c->regs[VCPU_REGS_RDX];
-	c->regs[VCPU_REGS_RSP] = c->regs[VCPU_REGS_RCX];
+	ctxt->_eip = ctxt->regs[VCPU_REGS_RDX];
+	ctxt->regs[VCPU_REGS_RSP] = ctxt->regs[VCPU_REGS_RCX];
 
 	return X86EMUL_CONTINUE;
 }
 
-static bool emulator_bad_iopl(struct x86_emulate_ctxt *ctxt,
-			      struct x86_emulate_ops *ops)
+static bool emulator_bad_iopl(struct x86_emulate_ctxt *ctxt)
 {
 	int iopl;
 	if (ctxt->mode == X86EMUL_MODE_REAL)
@@ -2071,13 +2023,13 @@ static bool emulator_bad_iopl(struct x86_emulate_ctxt *ctxt,
 	if (ctxt->mode == X86EMUL_MODE_VM86)
 		return true;
 	iopl = (ctxt->eflags & X86_EFLAGS_IOPL) >> IOPL_SHIFT;
-	return ops->cpl(ctxt) > iopl;
+	return ctxt->ops->cpl(ctxt) > iopl;
 }
 
 static bool emulator_io_port_access_allowed(struct x86_emulate_ctxt *ctxt,
-					    struct x86_emulate_ops *ops,
 					    u16 port, u16 len)
 {
+	struct x86_emulate_ops *ops = ctxt->ops;
 	struct desc_struct tr_seg;
 	u32 base3;
 	int r;
@@ -2108,14 +2060,13 @@ static bool emulator_io_port_access_allowed(struct x86_emulate_ctxt *ctxt,
 }
 
 static bool emulator_io_permited(struct x86_emulate_ctxt *ctxt,
-				 struct x86_emulate_ops *ops,
 				 u16 port, u16 len)
 {
 	if (ctxt->perm_ok)
 		return true;
 
-	if (emulator_bad_iopl(ctxt, ops))
-		if (!emulator_io_port_access_allowed(ctxt, ops, port, len))
+	if (emulator_bad_iopl(ctxt))
+		if (!emulator_io_port_access_allowed(ctxt, port, len))
 			return false;
 
 	ctxt->perm_ok = true;
@@ -2124,21 +2075,18 @@ static bool emulator_io_permited(struct x86_emulate_ctxt *ctxt,
 }
 
 static void save_state_to_tss16(struct x86_emulate_ctxt *ctxt,
-				struct x86_emulate_ops *ops,
 				struct tss_segment_16 *tss)
 {
-	struct decode_cache *c = &ctxt->decode;
-
-	tss->ip = c->eip;
+	tss->ip = ctxt->_eip;
 	tss->flag = ctxt->eflags;
-	tss->ax = c->regs[VCPU_REGS_RAX];
-	tss->cx = c->regs[VCPU_REGS_RCX];
-	tss->dx = c->regs[VCPU_REGS_RDX];
-	tss->bx = c->regs[VCPU_REGS_RBX];
-	tss->sp = c->regs[VCPU_REGS_RSP];
-	tss->bp = c->regs[VCPU_REGS_RBP];
-	tss->si = c->regs[VCPU_REGS_RSI];
-	tss->di = c->regs[VCPU_REGS_RDI];
+	tss->ax = ctxt->regs[VCPU_REGS_RAX];
+	tss->cx = ctxt->regs[VCPU_REGS_RCX];
+	tss->dx = ctxt->regs[VCPU_REGS_RDX];
+	tss->bx = ctxt->regs[VCPU_REGS_RBX];
+	tss->sp = ctxt->regs[VCPU_REGS_RSP];
+	tss->bp = ctxt->regs[VCPU_REGS_RBP];
+	tss->si = ctxt->regs[VCPU_REGS_RSI];
+	tss->di = ctxt->regs[VCPU_REGS_RDI];
 
 	tss->es = get_segment_selector(ctxt, VCPU_SREG_ES);
 	tss->cs = get_segment_selector(ctxt, VCPU_SREG_CS);
@@ -2148,22 +2096,20 @@ static void save_state_to_tss16(struct x86_emulate_ctxt *ctxt,
 }
 
 static int load_state_from_tss16(struct x86_emulate_ctxt *ctxt,
-				 struct x86_emulate_ops *ops,
 				 struct tss_segment_16 *tss)
 {
-	struct decode_cache *c = &ctxt->decode;
 	int ret;
 
-	c->eip = tss->ip;
+	ctxt->_eip = tss->ip;
 	ctxt->eflags = tss->flag | 2;
-	c->regs[VCPU_REGS_RAX] = tss->ax;
-	c->regs[VCPU_REGS_RCX] = tss->cx;
-	c->regs[VCPU_REGS_RDX] = tss->dx;
-	c->regs[VCPU_REGS_RBX] = tss->bx;
-	c->regs[VCPU_REGS_RSP] = tss->sp;
-	c->regs[VCPU_REGS_RBP] = tss->bp;
-	c->regs[VCPU_REGS_RSI] = tss->si;
-	c->regs[VCPU_REGS_RDI] = tss->di;
+	ctxt->regs[VCPU_REGS_RAX] = tss->ax;
+	ctxt->regs[VCPU_REGS_RCX] = tss->cx;
+	ctxt->regs[VCPU_REGS_RDX] = tss->dx;
+	ctxt->regs[VCPU_REGS_RBX] = tss->bx;
+	ctxt->regs[VCPU_REGS_RSP] = tss->sp;
+	ctxt->regs[VCPU_REGS_RBP] = tss->bp;
+	ctxt->regs[VCPU_REGS_RSI] = tss->si;
+	ctxt->regs[VCPU_REGS_RDI] = tss->di;
 
 	/*
 	 * SDM says that segment selectors are loaded before segment
@@ -2179,19 +2125,19 @@ static int load_state_from_tss16(struct x86_emulate_ctxt *ctxt,
 	 * Now load segment descriptors. If fault happenes at this stage
 	 * it is handled in a context of new task
 	 */
-	ret = load_segment_descriptor(ctxt, ops, tss->ldt, VCPU_SREG_LDTR);
+	ret = load_segment_descriptor(ctxt, tss->ldt, VCPU_SREG_LDTR);
 	if (ret != X86EMUL_CONTINUE)
 		return ret;
-	ret = load_segment_descriptor(ctxt, ops, tss->es, VCPU_SREG_ES);
+	ret = load_segment_descriptor(ctxt, tss->es, VCPU_SREG_ES);
 	if (ret != X86EMUL_CONTINUE)
 		return ret;
-	ret = load_segment_descriptor(ctxt, ops, tss->cs, VCPU_SREG_CS);
+	ret = load_segment_descriptor(ctxt, tss->cs, VCPU_SREG_CS);
 	if (ret != X86EMUL_CONTINUE)
 		return ret;
-	ret = load_segment_descriptor(ctxt, ops, tss->ss, VCPU_SREG_SS);
+	ret = load_segment_descriptor(ctxt, tss->ss, VCPU_SREG_SS);
 	if (ret != X86EMUL_CONTINUE)
 		return ret;
-	ret = load_segment_descriptor(ctxt, ops, tss->ds, VCPU_SREG_DS);
+	ret = load_segment_descriptor(ctxt, tss->ds, VCPU_SREG_DS);
 	if (ret != X86EMUL_CONTINUE)
 		return ret;
 
@@ -2199,10 +2145,10 @@ static int load_state_from_tss16(struct x86_emulate_ctxt *ctxt,
 }
 
 static int task_switch_16(struct x86_emulate_ctxt *ctxt,
-			  struct x86_emulate_ops *ops,
 			  u16 tss_selector, u16 old_tss_sel,
 			  ulong old_tss_base, struct desc_struct *new_desc)
 {
+	struct x86_emulate_ops *ops = ctxt->ops;
 	struct tss_segment_16 tss_seg;
 	int ret;
 	u32 new_tss_base = get_desc_base(new_desc);
@@ -2213,7 +2159,7 @@ static int task_switch_16(struct x86_emulate_ctxt *ctxt,
 		/* FIXME: need to provide precise fault address */
 		return ret;
 
-	save_state_to_tss16(ctxt, ops, &tss_seg);
+	save_state_to_tss16(ctxt, &tss_seg);
 
 	ret = ops->write_std(ctxt, old_tss_base, &tss_seg, sizeof tss_seg,
 			     &ctxt->exception);
@@ -2239,26 +2185,23 @@ static int task_switch_16(struct x86_emulate_ctxt *ctxt,
 			return ret;
 	}
 
-	return load_state_from_tss16(ctxt, ops, &tss_seg);
+	return load_state_from_tss16(ctxt, &tss_seg);
 }
 
 static void save_state_to_tss32(struct x86_emulate_ctxt *ctxt,
-				struct x86_emulate_ops *ops,
 				struct tss_segment_32 *tss)
 {
-	struct decode_cache *c = &ctxt->decode;
-
-	tss->cr3 = ops->get_cr(ctxt, 3);
-	tss->eip = c->eip;
+	tss->cr3 = ctxt->ops->get_cr(ctxt, 3);
+	tss->eip = ctxt->_eip;
 	tss->eflags = ctxt->eflags;
-	tss->eax = c->regs[VCPU_REGS_RAX];
-	tss->ecx = c->regs[VCPU_REGS_RCX];
-	tss->edx = c->regs[VCPU_REGS_RDX];
-	tss->ebx = c->regs[VCPU_REGS_RBX];
-	tss->esp = c->regs[VCPU_REGS_RSP];
-	tss->ebp = c->regs[VCPU_REGS_RBP];
-	tss->esi = c->regs[VCPU_REGS_RSI];
-	tss->edi = c->regs[VCPU_REGS_RDI];
+	tss->eax = ctxt->regs[VCPU_REGS_RAX];
+	tss->ecx = ctxt->regs[VCPU_REGS_RCX];
+	tss->edx = ctxt->regs[VCPU_REGS_RDX];
+	tss->ebx = ctxt->regs[VCPU_REGS_RBX];
+	tss->esp = ctxt->regs[VCPU_REGS_RSP];
+	tss->ebp = ctxt->regs[VCPU_REGS_RBP];
+	tss->esi = ctxt->regs[VCPU_REGS_RSI];
+	tss->edi = ctxt->regs[VCPU_REGS_RDI];
 
 	tss->es = get_segment_selector(ctxt, VCPU_SREG_ES);
 	tss->cs = get_segment_selector(ctxt, VCPU_SREG_CS);
@@ -2270,24 +2213,22 @@ static void save_state_to_tss32(struct x86_emulate_ctxt *ctxt,
 }
 
 static int load_state_from_tss32(struct x86_emulate_ctxt *ctxt,
-				 struct x86_emulate_ops *ops,
 				 struct tss_segment_32 *tss)
 {
-	struct decode_cache *c = &ctxt->decode;
 	int ret;
 
-	if (ops->set_cr(ctxt, 3, tss->cr3))
+	if (ctxt->ops->set_cr(ctxt, 3, tss->cr3))
 		return emulate_gp(ctxt, 0);
-	c->eip = tss->eip;
+	ctxt->_eip = tss->eip;
 	ctxt->eflags = tss->eflags | 2;
-	c->regs[VCPU_REGS_RAX] = tss->eax;
-	c->regs[VCPU_REGS_RCX] = tss->ecx;
-	c->regs[VCPU_REGS_RDX] = tss->edx;
-	c->regs[VCPU_REGS_RBX] = tss->ebx;
-	c->regs[VCPU_REGS_RSP] = tss->esp;
-	c->regs[VCPU_REGS_RBP] = tss->ebp;
-	c->regs[VCPU_REGS_RSI] = tss->esi;
-	c->regs[VCPU_REGS_RDI] = tss->edi;
+	ctxt->regs[VCPU_REGS_RAX] = tss->eax;
+	ctxt->regs[VCPU_REGS_RCX] = tss->ecx;
+	ctxt->regs[VCPU_REGS_RDX] = tss->edx;
+	ctxt->regs[VCPU_REGS_RBX] = tss->ebx;
+	ctxt->regs[VCPU_REGS_RSP] = tss->esp;
+	ctxt->regs[VCPU_REGS_RBP] = tss->ebp;
+	ctxt->regs[VCPU_REGS_RSI] = tss->esi;
+	ctxt->regs[VCPU_REGS_RDI] = tss->edi;
 
 	/*
 	 * SDM says that segment selectors are loaded before segment
@@ -2305,25 +2246,25 @@ static int load_state_from_tss32(struct x86_emulate_ctxt *ctxt,
 	 * Now load segment descriptors. If fault happenes at this stage
 	 * it is handled in a context of new task
 	 */
-	ret = load_segment_descriptor(ctxt, ops, tss->ldt_selector, VCPU_SREG_LDTR);
+	ret = load_segment_descriptor(ctxt, tss->ldt_selector, VCPU_SREG_LDTR);
 	if (ret != X86EMUL_CONTINUE)
 		return ret;
-	ret = load_segment_descriptor(ctxt, ops, tss->es, VCPU_SREG_ES);
+	ret = load_segment_descriptor(ctxt, tss->es, VCPU_SREG_ES);
 	if (ret != X86EMUL_CONTINUE)
 		return ret;
-	ret = load_segment_descriptor(ctxt, ops, tss->cs, VCPU_SREG_CS);
+	ret = load_segment_descriptor(ctxt, tss->cs, VCPU_SREG_CS);
 	if (ret != X86EMUL_CONTINUE)
 		return ret;
-	ret = load_segment_descriptor(ctxt, ops, tss->ss, VCPU_SREG_SS);
+	ret = load_segment_descriptor(ctxt, tss->ss, VCPU_SREG_SS);
 	if (ret != X86EMUL_CONTINUE)
 		return ret;
-	ret = load_segment_descriptor(ctxt, ops, tss->ds, VCPU_SREG_DS);
+	ret = load_segment_descriptor(ctxt, tss->ds, VCPU_SREG_DS);
 	if (ret != X86EMUL_CONTINUE)
 		return ret;
-	ret = load_segment_descriptor(ctxt, ops, tss->fs, VCPU_SREG_FS);
+	ret = load_segment_descriptor(ctxt, tss->fs, VCPU_SREG_FS);
 	if (ret != X86EMUL_CONTINUE)
 		return ret;
-	ret = load_segment_descriptor(ctxt, ops, tss->gs, VCPU_SREG_GS);
+	ret = load_segment_descriptor(ctxt, tss->gs, VCPU_SREG_GS);
 	if (ret != X86EMUL_CONTINUE)
 		return ret;
 
@@ -2331,10 +2272,10 @@ static int load_state_from_tss32(struct x86_emulate_ctxt *ctxt,
 }
 
 static int task_switch_32(struct x86_emulate_ctxt *ctxt,
-			  struct x86_emulate_ops *ops,
 			  u16 tss_selector, u16 old_tss_sel,
 			  ulong old_tss_base, struct desc_struct *new_desc)
 {
+	struct x86_emulate_ops *ops = ctxt->ops;
 	struct tss_segment_32 tss_seg;
 	int ret;
 	u32 new_tss_base = get_desc_base(new_desc);
@@ -2345,7 +2286,7 @@ static int task_switch_32(struct x86_emulate_ctxt *ctxt,
 		/* FIXME: need to provide precise fault address */
 		return ret;
 
-	save_state_to_tss32(ctxt, ops, &tss_seg);
+	save_state_to_tss32(ctxt, &tss_seg);
 
 	ret = ops->write_std(ctxt, old_tss_base, &tss_seg, sizeof tss_seg,
 			     &ctxt->exception);
@@ -2371,14 +2312,14 @@ static int task_switch_32(struct x86_emulate_ctxt *ctxt,
 			return ret;
 	}
 
-	return load_state_from_tss32(ctxt, ops, &tss_seg);
+	return load_state_from_tss32(ctxt, &tss_seg);
 }
 
 static int emulator_do_task_switch(struct x86_emulate_ctxt *ctxt,
-				   struct x86_emulate_ops *ops,
 				   u16 tss_selector, int reason,
 				   bool has_error_code, u32 error_code)
 {
+	struct x86_emulate_ops *ops = ctxt->ops;
 	struct desc_struct curr_tss_desc, next_tss_desc;
 	int ret;
 	u16 old_tss_sel = get_segment_selector(ctxt, VCPU_SREG_TR);
@@ -2388,10 +2329,10 @@ static int emulator_do_task_switch(struct x86_emulate_ctxt *ctxt,
 
 	/* FIXME: old_tss_base == ~0 ? */
 
-	ret = read_segment_descriptor(ctxt, ops, tss_selector, &next_tss_desc);
+	ret = read_segment_descriptor(ctxt, tss_selector, &next_tss_desc);
 	if (ret != X86EMUL_CONTINUE)
 		return ret;
-	ret = read_segment_descriptor(ctxt, ops, old_tss_sel, &curr_tss_desc);
+	ret = read_segment_descriptor(ctxt, old_tss_sel, &curr_tss_desc);
 	if (ret != X86EMUL_CONTINUE)
 		return ret;
 
@@ -2413,8 +2354,7 @@ static int emulator_do_task_switch(struct x86_emulate_ctxt *ctxt,
 
 	if (reason == TASK_SWITCH_IRET || reason == TASK_SWITCH_JMP) {
 		curr_tss_desc.type &= ~(1 << 1); /* clear busy flag */
-		write_segment_descriptor(ctxt, ops, old_tss_sel,
-					 &curr_tss_desc);
+		write_segment_descriptor(ctxt, old_tss_sel, &curr_tss_desc);
 	}
 
 	if (reason == TASK_SWITCH_IRET)
@@ -2426,10 +2366,10 @@ static int emulator_do_task_switch(struct x86_emulate_ctxt *ctxt,
 		old_tss_sel = 0xffff;
 
 	if (next_tss_desc.type & 8)
-		ret = task_switch_32(ctxt, ops, tss_selector, old_tss_sel,
+		ret = task_switch_32(ctxt, tss_selector, old_tss_sel,
 				     old_tss_base, &next_tss_desc);
 	else
-		ret = task_switch_16(ctxt, ops, tss_selector, old_tss_sel,
+		ret = task_switch_16(ctxt, tss_selector, old_tss_sel,
 				     old_tss_base, &next_tss_desc);
 	if (ret != X86EMUL_CONTINUE)
 		return ret;
@@ -2439,19 +2379,16 @@ static int emulator_do_task_switch(struct x86_emulate_ctxt *ctxt,
 
 	if (reason != TASK_SWITCH_IRET) {
 		next_tss_desc.type |= (1 << 1); /* set busy flag */
-		write_segment_descriptor(ctxt, ops, tss_selector,
-					 &next_tss_desc);
+		write_segment_descriptor(ctxt, tss_selector, &next_tss_desc);
 	}
 
 	ops->set_cr(ctxt, 0,  ops->get_cr(ctxt, 0) | X86_CR0_TS);
 	ops->set_segment(ctxt, tss_selector, &next_tss_desc, 0, VCPU_SREG_TR);
 
 	if (has_error_code) {
-		struct decode_cache *c = &ctxt->decode;
-
-		c->op_bytes = c->ad_bytes = (next_tss_desc.type & 8) ? 4 : 2;
-		c->lock_prefix = 0;
-		c->src.val = (unsigned long) error_code;
+		ctxt->op_bytes = ctxt->ad_bytes = (next_tss_desc.type & 8) ? 4 : 2;
+		ctxt->lock_prefix = 0;
+		ctxt->src.val = (unsigned long) error_code;
 		ret = em_push(ctxt);
 	}
 
@@ -2462,18 +2399,16 @@ int emulator_task_switch(struct x86_emulate_ctxt *ctxt,
 			 u16 tss_selector, int reason,
 			 bool has_error_code, u32 error_code)
 {
-	struct x86_emulate_ops *ops = ctxt->ops;
-	struct decode_cache *c = &ctxt->decode;
 	int rc;
 
-	c->eip = ctxt->eip;
-	c->dst.type = OP_NONE;
+	ctxt->_eip = ctxt->eip;
+	ctxt->dst.type = OP_NONE;
 
-	rc = emulator_do_task_switch(ctxt, ops, tss_selector, reason,
+	rc = emulator_do_task_switch(ctxt, tss_selector, reason,
 				     has_error_code, error_code);
 
 	if (rc == X86EMUL_CONTINUE)
-		ctxt->eip = c->eip;
+		ctxt->eip = ctxt->_eip;
 
 	return (rc == X86EMUL_UNHANDLEABLE) ? EMULATION_FAILED : EMULATION_OK;
 }
@@ -2481,22 +2416,20 @@ int emulator_task_switch(struct x86_emulate_ctxt *ctxt,
 static void string_addr_inc(struct x86_emulate_ctxt *ctxt, unsigned seg,
 			    int reg, struct operand *op)
 {
-	struct decode_cache *c = &ctxt->decode;
 	int df = (ctxt->eflags & EFLG_DF) ? -1 : 1;
 
-	register_address_increment(c, &c->regs[reg], df * op->bytes);
-	op->addr.mem.ea = register_address(c, c->regs[reg]);
+	register_address_increment(ctxt, &ctxt->regs[reg], df * op->bytes);
+	op->addr.mem.ea = register_address(ctxt, ctxt->regs[reg]);
 	op->addr.mem.seg = seg;
 }
 
 static int em_das(struct x86_emulate_ctxt *ctxt)
 {
-	struct decode_cache *c = &ctxt->decode;
 	u8 al, old_al;
 	bool af, cf, old_cf;
 
 	cf = ctxt->eflags & X86_EFLAGS_CF;
-	al = c->dst.val;
+	al = ctxt->dst.val;
 
 	old_al = al;
 	old_cf = cf;
@@ -2514,12 +2447,12 @@ static int em_das(struct x86_emulate_ctxt *ctxt)
 		cf = true;
 	}
 
-	c->dst.val = al;
+	ctxt->dst.val = al;
 	/* Set PF, ZF, SF */
-	c->src.type = OP_IMM;
-	c->src.val = 0;
-	c->src.bytes = 1;
-	emulate_2op_SrcV("or", c->src, c->dst, ctxt->eflags);
+	ctxt->src.type = OP_IMM;
+	ctxt->src.val = 0;
+	ctxt->src.bytes = 1;
+	emulate_2op_SrcV("or", ctxt->src, ctxt->dst, ctxt->eflags);
 	ctxt->eflags &= ~(X86_EFLAGS_AF | X86_EFLAGS_CF);
 	if (cf)
 		ctxt->eflags |= X86_EFLAGS_CF;
@@ -2530,175 +2463,189 @@ static int em_das(struct x86_emulate_ctxt *ctxt)
 
 static int em_call_far(struct x86_emulate_ctxt *ctxt)
 {
-	struct decode_cache *c = &ctxt->decode;
 	u16 sel, old_cs;
 	ulong old_eip;
 	int rc;
 
 	old_cs = get_segment_selector(ctxt, VCPU_SREG_CS);
-	old_eip = c->eip;
+	old_eip = ctxt->_eip;
 
-	memcpy(&sel, c->src.valptr + c->op_bytes, 2);
-	if (load_segment_descriptor(ctxt, ctxt->ops, sel, VCPU_SREG_CS))
+	memcpy(&sel, ctxt->src.valptr + ctxt->op_bytes, 2);
+	if (load_segment_descriptor(ctxt, sel, VCPU_SREG_CS))
 		return X86EMUL_CONTINUE;
 
-	c->eip = 0;
-	memcpy(&c->eip, c->src.valptr, c->op_bytes);
+	ctxt->_eip = 0;
+	memcpy(&ctxt->_eip, ctxt->src.valptr, ctxt->op_bytes);
 
-	c->src.val = old_cs;
+	ctxt->src.val = old_cs;
 	rc = em_push(ctxt);
 	if (rc != X86EMUL_CONTINUE)
 		return rc;
 
-	c->src.val = old_eip;
+	ctxt->src.val = old_eip;
 	return em_push(ctxt);
 }
 
 static int em_ret_near_imm(struct x86_emulate_ctxt *ctxt)
 {
-	struct decode_cache *c = &ctxt->decode;
 	int rc;
 
-	c->dst.type = OP_REG;
-	c->dst.addr.reg = &c->eip;
-	c->dst.bytes = c->op_bytes;
-	rc = emulate_pop(ctxt, &c->dst.val, c->op_bytes);
+	ctxt->dst.type = OP_REG;
+	ctxt->dst.addr.reg = &ctxt->_eip;
+	ctxt->dst.bytes = ctxt->op_bytes;
+	rc = emulate_pop(ctxt, &ctxt->dst.val, ctxt->op_bytes);
 	if (rc != X86EMUL_CONTINUE)
 		return rc;
-	register_address_increment(c, &c->regs[VCPU_REGS_RSP], c->src.val);
+	register_address_increment(ctxt, &ctxt->regs[VCPU_REGS_RSP], ctxt->src.val);
 	return X86EMUL_CONTINUE;
 }
 
 static int em_add(struct x86_emulate_ctxt *ctxt)
 {
-	struct decode_cache *c = &ctxt->decode;
-
-	emulate_2op_SrcV("add", c->src, c->dst, ctxt->eflags);
+	emulate_2op_SrcV("add", ctxt->src, ctxt->dst, ctxt->eflags);
 	return X86EMUL_CONTINUE;
 }
 
 static int em_or(struct x86_emulate_ctxt *ctxt)
 {
-	struct decode_cache *c = &ctxt->decode;
-
-	emulate_2op_SrcV("or", c->src, c->dst, ctxt->eflags);
+	emulate_2op_SrcV("or", ctxt->src, ctxt->dst, ctxt->eflags);
 	return X86EMUL_CONTINUE;
 }
 
 static int em_adc(struct x86_emulate_ctxt *ctxt)
 {
-	struct decode_cache *c = &ctxt->decode;
-
-	emulate_2op_SrcV("adc", c->src, c->dst, ctxt->eflags);
+	emulate_2op_SrcV("adc", ctxt->src, ctxt->dst, ctxt->eflags);
 	return X86EMUL_CONTINUE;
 }
 
 static int em_sbb(struct x86_emulate_ctxt *ctxt)
 {
-	struct decode_cache *c = &ctxt->decode;
-
-	emulate_2op_SrcV("sbb", c->src, c->dst, ctxt->eflags);
+	emulate_2op_SrcV("sbb", ctxt->src, ctxt->dst, ctxt->eflags);
 	return X86EMUL_CONTINUE;
 }
 
 static int em_and(struct x86_emulate_ctxt *ctxt)
 {
-	struct decode_cache *c = &ctxt->decode;
-
-	emulate_2op_SrcV("and", c->src, c->dst, ctxt->eflags);
+	emulate_2op_SrcV("and", ctxt->src, ctxt->dst, ctxt->eflags);
 	return X86EMUL_CONTINUE;
 }
 
 static int em_sub(struct x86_emulate_ctxt *ctxt)
 {
-	struct decode_cache *c = &ctxt->decode;
-
-	emulate_2op_SrcV("sub", c->src, c->dst, ctxt->eflags);
+	emulate_2op_SrcV("sub", ctxt->src, ctxt->dst, ctxt->eflags);
 	return X86EMUL_CONTINUE;
 }
 
 static int em_xor(struct x86_emulate_ctxt *ctxt)
 {
-	struct decode_cache *c = &ctxt->decode;
-
-	emulate_2op_SrcV("xor", c->src, c->dst, ctxt->eflags);
+	emulate_2op_SrcV("xor", ctxt->src, ctxt->dst, ctxt->eflags);
 	return X86EMUL_CONTINUE;
 }
 
 static int em_cmp(struct x86_emulate_ctxt *ctxt)
 {
-	struct decode_cache *c = &ctxt->decode;
-
-	emulate_2op_SrcV("cmp", c->src, c->dst, ctxt->eflags);
+	emulate_2op_SrcV("cmp", ctxt->src, ctxt->dst, ctxt->eflags);
 	/* Disable writeback. */
-	c->dst.type = OP_NONE;
+	ctxt->dst.type = OP_NONE;
 	return X86EMUL_CONTINUE;
 }
 
-static int em_imul(struct x86_emulate_ctxt *ctxt)
+static int em_test(struct x86_emulate_ctxt *ctxt)
+{
+	emulate_2op_SrcV("test", ctxt->src, ctxt->dst, ctxt->eflags);
+	return X86EMUL_CONTINUE;
+}
+
+static int em_xchg(struct x86_emulate_ctxt *ctxt)
 {
-	struct decode_cache *c = &ctxt->decode;
+	/* Write back the register source. */
+	ctxt->src.val = ctxt->dst.val;
+	write_register_operand(&ctxt->src);
 
-	emulate_2op_SrcV_nobyte("imul", c->src, c->dst, ctxt->eflags);
+	/* Write back the memory destination with implicit LOCK prefix. */
+	ctxt->dst.val = ctxt->src.orig_val;
+	ctxt->lock_prefix = 1;
 	return X86EMUL_CONTINUE;
 }
 
-static int em_imul_3op(struct x86_emulate_ctxt *ctxt)
+static int em_imul(struct x86_emulate_ctxt *ctxt)
 {
-	struct decode_cache *c = &ctxt->decode;
+	emulate_2op_SrcV_nobyte("imul", ctxt->src, ctxt->dst, ctxt->eflags);
+	return X86EMUL_CONTINUE;
+}
 
-	c->dst.val = c->src2.val;
+static int em_imul_3op(struct x86_emulate_ctxt *ctxt)
+{
+	ctxt->dst.val = ctxt->src2.val;
 	return em_imul(ctxt);
 }
 
 static int em_cwd(struct x86_emulate_ctxt *ctxt)
 {
-	struct decode_cache *c = &ctxt->decode;
-
-	c->dst.type = OP_REG;
-	c->dst.bytes = c->src.bytes;
-	c->dst.addr.reg = &c->regs[VCPU_REGS_RDX];
-	c->dst.val = ~((c->src.val >> (c->src.bytes * 8 - 1)) - 1);
+	ctxt->dst.type = OP_REG;
+	ctxt->dst.bytes = ctxt->src.bytes;
+	ctxt->dst.addr.reg = &ctxt->regs[VCPU_REGS_RDX];
+	ctxt->dst.val = ~((ctxt->src.val >> (ctxt->src.bytes * 8 - 1)) - 1);
 
 	return X86EMUL_CONTINUE;
 }
 
 static int em_rdtsc(struct x86_emulate_ctxt *ctxt)
 {
-	struct decode_cache *c = &ctxt->decode;
 	u64 tsc = 0;
 
 	ctxt->ops->get_msr(ctxt, MSR_IA32_TSC, &tsc);
-	c->regs[VCPU_REGS_RAX] = (u32)tsc;
-	c->regs[VCPU_REGS_RDX] = tsc >> 32;
+	ctxt->regs[VCPU_REGS_RAX] = (u32)tsc;
+	ctxt->regs[VCPU_REGS_RDX] = tsc >> 32;
 	return X86EMUL_CONTINUE;
 }
 
 static int em_mov(struct x86_emulate_ctxt *ctxt)
 {
-	struct decode_cache *c = &ctxt->decode;
-	c->dst.val = c->src.val;
+	ctxt->dst.val = ctxt->src.val;
 	return X86EMUL_CONTINUE;
 }
 
+static int em_mov_rm_sreg(struct x86_emulate_ctxt *ctxt)
+{
+	if (ctxt->modrm_reg > VCPU_SREG_GS)
+		return emulate_ud(ctxt);
+
+	ctxt->dst.val = get_segment_selector(ctxt, ctxt->modrm_reg);
+	return X86EMUL_CONTINUE;
+}
+
+static int em_mov_sreg_rm(struct x86_emulate_ctxt *ctxt)
+{
+	u16 sel = ctxt->src.val;
+
+	if (ctxt->modrm_reg == VCPU_SREG_CS || ctxt->modrm_reg > VCPU_SREG_GS)
+		return emulate_ud(ctxt);
+
+	if (ctxt->modrm_reg == VCPU_SREG_SS)
+		ctxt->interruptibility = KVM_X86_SHADOW_INT_MOV_SS;
+
+	/* Disable writeback. */
+	ctxt->dst.type = OP_NONE;
+	return load_segment_descriptor(ctxt, sel, ctxt->modrm_reg);
+}
+
 static int em_movdqu(struct x86_emulate_ctxt *ctxt)
 {
-	struct decode_cache *c = &ctxt->decode;
-	memcpy(&c->dst.vec_val, &c->src.vec_val, c->op_bytes);
+	memcpy(&ctxt->dst.vec_val, &ctxt->src.vec_val, ctxt->op_bytes);
 	return X86EMUL_CONTINUE;
 }
 
 static int em_invlpg(struct x86_emulate_ctxt *ctxt)
 {
-	struct decode_cache *c = &ctxt->decode;
 	int rc;
 	ulong linear;
 
-	rc = linearize(ctxt, c->src.addr.mem, 1, false, &linear);
+	rc = linearize(ctxt, ctxt->src.addr.mem, 1, false, &linear);
 	if (rc == X86EMUL_CONTINUE)
 		ctxt->ops->invlpg(ctxt, linear);
 	/* Disable writeback. */
-	c->dst.type = OP_NONE;
+	ctxt->dst.type = OP_NONE;
 	return X86EMUL_CONTINUE;
 }
 
@@ -2714,10 +2661,9 @@ static int em_clts(struct x86_emulate_ctxt *ctxt)
 
 static int em_vmcall(struct x86_emulate_ctxt *ctxt)
 {
-	struct decode_cache *c = &ctxt->decode;
 	int rc;
 
-	if (c->modrm_mod != 3 || c->modrm_rm != 1)
+	if (ctxt->modrm_mod != 3 || ctxt->modrm_rm != 1)
 		return X86EMUL_UNHANDLEABLE;
 
 	rc = ctxt->ops->fix_hypercall(ctxt);
@@ -2725,73 +2671,104 @@ static int em_vmcall(struct x86_emulate_ctxt *ctxt)
 		return rc;
 
 	/* Let the processor re-execute the fixed hypercall */
-	c->eip = ctxt->eip;
+	ctxt->_eip = ctxt->eip;
 	/* Disable writeback. */
-	c->dst.type = OP_NONE;
+	ctxt->dst.type = OP_NONE;
 	return X86EMUL_CONTINUE;
 }
 
 static int em_lgdt(struct x86_emulate_ctxt *ctxt)
 {
-	struct decode_cache *c = &ctxt->decode;
 	struct desc_ptr desc_ptr;
 	int rc;
 
-	rc = read_descriptor(ctxt, c->src.addr.mem,
+	rc = read_descriptor(ctxt, ctxt->src.addr.mem,
 			     &desc_ptr.size, &desc_ptr.address,
-			     c->op_bytes);
+			     ctxt->op_bytes);
 	if (rc != X86EMUL_CONTINUE)
 		return rc;
 	ctxt->ops->set_gdt(ctxt, &desc_ptr);
 	/* Disable writeback. */
-	c->dst.type = OP_NONE;
+	ctxt->dst.type = OP_NONE;
 	return X86EMUL_CONTINUE;
 }
 
 static int em_vmmcall(struct x86_emulate_ctxt *ctxt)
 {
-	struct decode_cache *c = &ctxt->decode;
 	int rc;
 
 	rc = ctxt->ops->fix_hypercall(ctxt);
 
 	/* Disable writeback. */
-	c->dst.type = OP_NONE;
+	ctxt->dst.type = OP_NONE;
 	return rc;
 }
 
 static int em_lidt(struct x86_emulate_ctxt *ctxt)
 {
-	struct decode_cache *c = &ctxt->decode;
 	struct desc_ptr desc_ptr;
 	int rc;
 
-	rc = read_descriptor(ctxt, c->src.addr.mem,
+	rc = read_descriptor(ctxt, ctxt->src.addr.mem,
 			     &desc_ptr.size, &desc_ptr.address,
-			     c->op_bytes);
+			     ctxt->op_bytes);
 	if (rc != X86EMUL_CONTINUE)
 		return rc;
 	ctxt->ops->set_idt(ctxt, &desc_ptr);
 	/* Disable writeback. */
-	c->dst.type = OP_NONE;
+	ctxt->dst.type = OP_NONE;
 	return X86EMUL_CONTINUE;
 }
 
 static int em_smsw(struct x86_emulate_ctxt *ctxt)
 {
-	struct decode_cache *c = &ctxt->decode;
-
-	c->dst.bytes = 2;
-	c->dst.val = ctxt->ops->get_cr(ctxt, 0);
+	ctxt->dst.bytes = 2;
+	ctxt->dst.val = ctxt->ops->get_cr(ctxt, 0);
 	return X86EMUL_CONTINUE;
 }
 
 static int em_lmsw(struct x86_emulate_ctxt *ctxt)
 {
-	struct decode_cache *c = &ctxt->decode;
 	ctxt->ops->set_cr(ctxt, 0, (ctxt->ops->get_cr(ctxt, 0) & ~0x0eul)
-			  | (c->src.val & 0x0f));
-	c->dst.type = OP_NONE;
+			  | (ctxt->src.val & 0x0f));
+	ctxt->dst.type = OP_NONE;
+	return X86EMUL_CONTINUE;
+}
+
+static int em_loop(struct x86_emulate_ctxt *ctxt)
+{
+	register_address_increment(ctxt, &ctxt->regs[VCPU_REGS_RCX], -1);
+	if ((address_mask(ctxt, ctxt->regs[VCPU_REGS_RCX]) != 0) &&
+	    (ctxt->b == 0xe2 || test_cc(ctxt->b ^ 0x5, ctxt->eflags)))
+		jmp_rel(ctxt, ctxt->src.val);
+
+	return X86EMUL_CONTINUE;
+}
+
+static int em_jcxz(struct x86_emulate_ctxt *ctxt)
+{
+	if (address_mask(ctxt, ctxt->regs[VCPU_REGS_RCX]) == 0)
+		jmp_rel(ctxt, ctxt->src.val);
+
+	return X86EMUL_CONTINUE;
+}
+
+static int em_cli(struct x86_emulate_ctxt *ctxt)
+{
+	if (emulator_bad_iopl(ctxt))
+		return emulate_gp(ctxt, 0);
+
+	ctxt->eflags &= ~X86_EFLAGS_IF;
+	return X86EMUL_CONTINUE;
+}
+
+static int em_sti(struct x86_emulate_ctxt *ctxt)
+{
+	if (emulator_bad_iopl(ctxt))
+		return emulate_gp(ctxt, 0);
+
+	ctxt->interruptibility = KVM_X86_SHADOW_INT_STI;
+	ctxt->eflags |= X86_EFLAGS_IF;
 	return X86EMUL_CONTINUE;
 }
 
@@ -2809,9 +2786,7 @@ static bool valid_cr(int nr)
 
 static int check_cr_read(struct x86_emulate_ctxt *ctxt)
 {
-	struct decode_cache *c = &ctxt->decode;
-
-	if (!valid_cr(c->modrm_reg))
+	if (!valid_cr(ctxt->modrm_reg))
 		return emulate_ud(ctxt);
 
 	return X86EMUL_CONTINUE;
@@ -2819,9 +2794,8 @@ static int check_cr_read(struct x86_emulate_ctxt *ctxt)
 
 static int check_cr_write(struct x86_emulate_ctxt *ctxt)
 {
-	struct decode_cache *c = &ctxt->decode;
-	u64 new_val = c->src.val64;
-	int cr = c->modrm_reg;
+	u64 new_val = ctxt->src.val64;
+	int cr = ctxt->modrm_reg;
 	u64 efer = 0;
 
 	static u64 cr_reserved_bits[] = {
@@ -2898,8 +2872,7 @@ static int check_dr7_gd(struct x86_emulate_ctxt *ctxt)
 
 static int check_dr_read(struct x86_emulate_ctxt *ctxt)
 {
-	struct decode_cache *c = &ctxt->decode;
-	int dr = c->modrm_reg;
+	int dr = ctxt->modrm_reg;
 	u64 cr4;
 
 	if (dr > 7)
@@ -2917,9 +2890,8 @@ static int check_dr_read(struct x86_emulate_ctxt *ctxt)
 
 static int check_dr_write(struct x86_emulate_ctxt *ctxt)
 {
-	struct decode_cache *c = &ctxt->decode;
-	u64 new_val = c->src.val64;
-	int dr = c->modrm_reg;
+	u64 new_val = ctxt->src.val64;
+	int dr = ctxt->modrm_reg;
 
 	if ((dr == 6 || dr == 7) && (new_val & 0xffffffff00000000ULL))
 		return emulate_gp(ctxt, 0);
@@ -2941,7 +2913,7 @@ static int check_svme(struct x86_emulate_ctxt *ctxt)
 
 static int check_svme_pa(struct x86_emulate_ctxt *ctxt)
 {
-	u64 rax = ctxt->decode.regs[VCPU_REGS_RAX];
+	u64 rax = ctxt->regs[VCPU_REGS_RAX];
 
 	/* Valid physical address? */
 	if (rax & 0xffff000000000000ULL)
@@ -2963,7 +2935,7 @@ static int check_rdtsc(struct x86_emulate_ctxt *ctxt)
 static int check_rdpmc(struct x86_emulate_ctxt *ctxt)
 {
 	u64 cr4 = ctxt->ops->get_cr(ctxt, 4);
-	u64 rcx = ctxt->decode.regs[VCPU_REGS_RCX];
+	u64 rcx = ctxt->regs[VCPU_REGS_RCX];
 
 	if ((!(cr4 & X86_CR4_PCE) && ctxt->ops->cpl(ctxt)) ||
 	    (rcx > 3))
@@ -2974,10 +2946,8 @@ static int check_rdpmc(struct x86_emulate_ctxt *ctxt)
 
 static int check_perm_in(struct x86_emulate_ctxt *ctxt)
 {
-	struct decode_cache *c = &ctxt->decode;
-
-	c->dst.bytes = min(c->dst.bytes, 4u);
-	if (!emulator_io_permited(ctxt, ctxt->ops, c->src.val, c->dst.bytes))
+	ctxt->dst.bytes = min(ctxt->dst.bytes, 4u);
+	if (!emulator_io_permited(ctxt, ctxt->src.val, ctxt->dst.bytes))
 		return emulate_gp(ctxt, 0);
 
 	return X86EMUL_CONTINUE;
@@ -2985,10 +2955,8 @@ static int check_perm_in(struct x86_emulate_ctxt *ctxt)
 
 static int check_perm_out(struct x86_emulate_ctxt *ctxt)
 {
-	struct decode_cache *c = &ctxt->decode;
-
-	c->src.bytes = min(c->src.bytes, 4u);
-	if (!emulator_io_permited(ctxt, ctxt->ops, c->dst.val, c->src.bytes))
+	ctxt->src.bytes = min(ctxt->src.bytes, 4u);
+	if (!emulator_io_permited(ctxt, ctxt->dst.val, ctxt->src.bytes))
 		return emulate_gp(ctxt, 0);
 
 	return X86EMUL_CONTINUE;
@@ -3165,12 +3133,15 @@ static struct opcode opcode_table[256] = {
 	G(DstMem | SrcImm | ModRM | Group, group1),
 	G(ByteOp | DstMem | SrcImm | ModRM | No64 | Group, group1),
 	G(DstMem | SrcImmByte | ModRM | Group, group1),
-	D2bv(DstMem | SrcReg | ModRM), D2bv(DstMem | SrcReg | ModRM | Lock),
+	I2bv(DstMem | SrcReg | ModRM, em_test),
+	I2bv(DstMem | SrcReg | ModRM | Lock, em_xchg),
 	/* 0x88 - 0x8F */
 	I2bv(DstMem | SrcReg | ModRM | Mov, em_mov),
 	I2bv(DstReg | SrcMem | ModRM | Mov, em_mov),
-	D(DstMem | SrcNone | ModRM | Mov), D(ModRM | SrcMem | NoAccess | DstReg),
-	D(ImplicitOps | SrcMem16 | ModRM), G(0, group1A),
+	I(DstMem | SrcNone | ModRM | Mov, em_mov_rm_sreg),
+	D(ModRM | SrcMem | NoAccess | DstReg),
+	I(ImplicitOps | SrcMem16 | ModRM, em_mov_sreg_rm),
+	G(0, group1A),
 	/* 0x90 - 0x97 */
 	DI(SrcAcc | DstReg, pause), X7(D(SrcAcc | DstReg)),
 	/* 0x98 - 0x9F */
@@ -3184,7 +3155,7 @@ static struct opcode opcode_table[256] = {
 	I2bv(SrcSI | DstDI | Mov | String, em_mov),
 	I2bv(SrcSI | DstDI | String, em_cmp),
 	/* 0xA8 - 0xAF */
-	D2bv(DstAcc | SrcImm),
+	I2bv(DstAcc | SrcImm, em_test),
 	I2bv(SrcAcc | DstDI | Mov | String, em_mov),
 	I2bv(SrcSI | DstAcc | Mov | String, em_mov),
 	I2bv(SrcAcc | DstDI | String, em_cmp),
@@ -3195,25 +3166,26 @@ static struct opcode opcode_table[256] = {
 	/* 0xC0 - 0xC7 */
 	D2bv(DstMem | SrcImmByte | ModRM),
 	I(ImplicitOps | Stack | SrcImmU16, em_ret_near_imm),
-	D(ImplicitOps | Stack),
+	I(ImplicitOps | Stack, em_ret),
 	D(DstReg | SrcMemFAddr | ModRM | No64), D(DstReg | SrcMemFAddr | ModRM | No64),
 	G(ByteOp, group11), G(0, group11),
 	/* 0xC8 - 0xCF */
-	N, N, N, D(ImplicitOps | Stack),
+	N, N, N, I(ImplicitOps | Stack, em_ret_far),
 	D(ImplicitOps), DI(SrcImmByte, intn),
-	D(ImplicitOps | No64), DI(ImplicitOps, iret),
+	D(ImplicitOps | No64), II(ImplicitOps, em_iret, iret),
 	/* 0xD0 - 0xD7 */
 	D2bv(DstMem | SrcOne | ModRM), D2bv(DstMem | ModRM),
 	N, N, N, N,
 	/* 0xD8 - 0xDF */
 	N, N, N, N, N, N, N, N,
 	/* 0xE0 - 0xE7 */
-	X4(D(SrcImmByte)),
+	X3(I(SrcImmByte, em_loop)),
+	I(SrcImmByte, em_jcxz),
 	D2bvIP(SrcImmUByte | DstAcc, in,  check_perm_in),
 	D2bvIP(SrcAcc | DstImmUByte, out, check_perm_out),
 	/* 0xE8 - 0xEF */
 	D(SrcImm | Stack), D(SrcImm | ImplicitOps),
-	D(SrcImmFAddr | No64), D(SrcImmByte | ImplicitOps),
+	I(SrcImmFAddr | No64, em_jmp_far), D(SrcImmByte | ImplicitOps),
 	D2bvIP(SrcDX | DstAcc, in,  check_perm_in),
 	D2bvIP(SrcAcc | DstDX, out, check_perm_out),
 	/* 0xF0 - 0xF7 */
@@ -3221,14 +3193,16 @@ static struct opcode opcode_table[256] = {
 	DI(ImplicitOps | Priv, hlt), D(ImplicitOps),
 	G(ByteOp, group3), G(0, group3),
 	/* 0xF8 - 0xFF */
-	D(ImplicitOps), D(ImplicitOps), D(ImplicitOps), D(ImplicitOps),
+	D(ImplicitOps), D(ImplicitOps),
+	I(ImplicitOps, em_cli), I(ImplicitOps, em_sti),
 	D(ImplicitOps), D(ImplicitOps), G(0, group4), G(0, group5),
 };
 
 static struct opcode twobyte_table[256] = {
 	/* 0x00 - 0x0F */
 	G(0, group6), GD(0, &group7), N, N,
-	N, D(ImplicitOps | VendorSpecific), DI(ImplicitOps | Priv, clts), N,
+	N, I(ImplicitOps | VendorSpecific, em_syscall),
+	II(ImplicitOps | Priv, em_clts, clts), N,
 	DI(ImplicitOps | Priv, invd), DI(ImplicitOps | Priv, wbinvd), N, N,
 	N, D(ImplicitOps | ModRM), N, N,
 	/* 0x10 - 0x1F */
@@ -3245,7 +3219,8 @@ static struct opcode twobyte_table[256] = {
 	IIP(ImplicitOps, em_rdtsc, rdtsc, check_rdtsc),
 	DI(ImplicitOps | Priv, rdmsr),
 	DIP(ImplicitOps | Priv, rdpmc, check_rdpmc),
-	D(ImplicitOps | VendorSpecific), D(ImplicitOps | Priv | VendorSpecific),
+	I(ImplicitOps | VendorSpecific, em_sysenter),
+	I(ImplicitOps | Priv | VendorSpecific, em_sysexit),
 	N, N,
 	N, N, N, N, N, N, N, N,
 	/* 0x40 - 0x4F */
@@ -3313,11 +3288,11 @@ static struct opcode twobyte_table[256] = {
 #undef I2bv
 #undef I6ALU
 
-static unsigned imm_size(struct decode_cache *c)
+static unsigned imm_size(struct x86_emulate_ctxt *ctxt)
 {
 	unsigned size;
 
-	size = (c->d & ByteOp) ? 1 : c->op_bytes;
+	size = (ctxt->d & ByteOp) ? 1 : ctxt->op_bytes;
 	if (size == 8)
 		size = 4;
 	return size;
@@ -3326,23 +3301,21 @@ static unsigned imm_size(struct decode_cache *c)
 static int decode_imm(struct x86_emulate_ctxt *ctxt, struct operand *op,
 		      unsigned size, bool sign_extension)
 {
-	struct decode_cache *c = &ctxt->decode;
-	struct x86_emulate_ops *ops = ctxt->ops;
 	int rc = X86EMUL_CONTINUE;
 
 	op->type = OP_IMM;
 	op->bytes = size;
-	op->addr.mem.ea = c->eip;
+	op->addr.mem.ea = ctxt->_eip;
 	/* NB. Immediates are sign-extended as necessary. */
 	switch (op->bytes) {
 	case 1:
-		op->val = insn_fetch(s8, 1, c->eip);
+		op->val = insn_fetch(s8, 1, ctxt->_eip);
 		break;
 	case 2:
-		op->val = insn_fetch(s16, 2, c->eip);
+		op->val = insn_fetch(s16, 2, ctxt->_eip);
 		break;
 	case 4:
-		op->val = insn_fetch(s32, 4, c->eip);
+		op->val = insn_fetch(s32, 4, ctxt->_eip);
 		break;
 	}
 	if (!sign_extension) {
@@ -3362,11 +3335,8 @@ done:
 	return rc;
 }
 
-int
-x86_decode_insn(struct x86_emulate_ctxt *ctxt, void *insn, int insn_len)
+int x86_decode_insn(struct x86_emulate_ctxt *ctxt, void *insn, int insn_len)
 {
-	struct x86_emulate_ops *ops = ctxt->ops;
-	struct decode_cache *c = &ctxt->decode;
 	int rc = X86EMUL_CONTINUE;
 	int mode = ctxt->mode;
 	int def_op_bytes, def_ad_bytes, goffset, simd_prefix;
@@ -3374,11 +3344,11 @@ x86_decode_insn(struct x86_emulate_ctxt *ctxt, void *insn, int insn_len)
 	struct opcode opcode;
 	struct operand memop = { .type = OP_NONE }, *memopp = NULL;
 
-	c->eip = ctxt->eip;
-	c->fetch.start = c->eip;
-	c->fetch.end = c->fetch.start + insn_len;
+	ctxt->_eip = ctxt->eip;
+	ctxt->fetch.start = ctxt->_eip;
+	ctxt->fetch.end = ctxt->fetch.start + insn_len;
 	if (insn_len > 0)
-		memcpy(c->fetch.data, insn, insn_len);
+		memcpy(ctxt->fetch.data, insn, insn_len);
 
 	switch (mode) {
 	case X86EMUL_MODE_REAL:
@@ -3399,46 +3369,46 @@ x86_decode_insn(struct x86_emulate_ctxt *ctxt, void *insn, int insn_len)
 		return -1;
 	}
 
-	c->op_bytes = def_op_bytes;
-	c->ad_bytes = def_ad_bytes;
+	ctxt->op_bytes = def_op_bytes;
+	ctxt->ad_bytes = def_ad_bytes;
 
 	/* Legacy prefixes. */
 	for (;;) {
-		switch (c->b = insn_fetch(u8, 1, c->eip)) {
+		switch (ctxt->b = insn_fetch(u8, 1, ctxt->_eip)) {
 		case 0x66:	/* operand-size override */
 			op_prefix = true;
 			/* switch between 2/4 bytes */
-			c->op_bytes = def_op_bytes ^ 6;
+			ctxt->op_bytes = def_op_bytes ^ 6;
 			break;
 		case 0x67:	/* address-size override */
 			if (mode == X86EMUL_MODE_PROT64)
 				/* switch between 4/8 bytes */
-				c->ad_bytes = def_ad_bytes ^ 12;
+				ctxt->ad_bytes = def_ad_bytes ^ 12;
 			else
 				/* switch between 2/4 bytes */
-				c->ad_bytes = def_ad_bytes ^ 6;
+				ctxt->ad_bytes = def_ad_bytes ^ 6;
 			break;
 		case 0x26:	/* ES override */
 		case 0x2e:	/* CS override */
 		case 0x36:	/* SS override */
 		case 0x3e:	/* DS override */
-			set_seg_override(c, (c->b >> 3) & 3);
+			set_seg_override(ctxt, (ctxt->b >> 3) & 3);
 			break;
 		case 0x64:	/* FS override */
 		case 0x65:	/* GS override */
-			set_seg_override(c, c->b & 7);
+			set_seg_override(ctxt, ctxt->b & 7);
 			break;
 		case 0x40 ... 0x4f: /* REX */
 			if (mode != X86EMUL_MODE_PROT64)
 				goto done_prefixes;
-			c->rex_prefix = c->b;
+			ctxt->rex_prefix = ctxt->b;
 			continue;
 		case 0xf0:	/* LOCK */
-			c->lock_prefix = 1;
+			ctxt->lock_prefix = 1;
 			break;
 		case 0xf2:	/* REPNE/REPNZ */
 		case 0xf3:	/* REP/REPE/REPZ */
-			c->rep_prefix = c->b;
+			ctxt->rep_prefix = ctxt->b;
 			break;
 		default:
 			goto done_prefixes;
@@ -3446,50 +3416,50 @@ x86_decode_insn(struct x86_emulate_ctxt *ctxt, void *insn, int insn_len)
 
 		/* Any legacy prefix after a REX prefix nullifies its effect. */
 
-		c->rex_prefix = 0;
+		ctxt->rex_prefix = 0;
 	}
 
 done_prefixes:
 
 	/* REX prefix. */
-	if (c->rex_prefix & 8)
-		c->op_bytes = 8;	/* REX.W */
+	if (ctxt->rex_prefix & 8)
+		ctxt->op_bytes = 8;	/* REX.W */
 
 	/* Opcode byte(s). */
-	opcode = opcode_table[c->b];
+	opcode = opcode_table[ctxt->b];
 	/* Two-byte opcode? */
-	if (c->b == 0x0f) {
-		c->twobyte = 1;
-		c->b = insn_fetch(u8, 1, c->eip);
-		opcode = twobyte_table[c->b];
+	if (ctxt->b == 0x0f) {
+		ctxt->twobyte = 1;
+		ctxt->b = insn_fetch(u8, 1, ctxt->_eip);
+		opcode = twobyte_table[ctxt->b];
 	}
-	c->d = opcode.flags;
+	ctxt->d = opcode.flags;
 
-	while (c->d & GroupMask) {
-		switch (c->d & GroupMask) {
+	while (ctxt->d & GroupMask) {
+		switch (ctxt->d & GroupMask) {
 		case Group:
-			c->modrm = insn_fetch(u8, 1, c->eip);
-			--c->eip;
-			goffset = (c->modrm >> 3) & 7;
+			ctxt->modrm = insn_fetch(u8, 1, ctxt->_eip);
+			--ctxt->_eip;
+			goffset = (ctxt->modrm >> 3) & 7;
 			opcode = opcode.u.group[goffset];
 			break;
 		case GroupDual:
-			c->modrm = insn_fetch(u8, 1, c->eip);
-			--c->eip;
-			goffset = (c->modrm >> 3) & 7;
-			if ((c->modrm >> 6) == 3)
+			ctxt->modrm = insn_fetch(u8, 1, ctxt->_eip);
+			--ctxt->_eip;
+			goffset = (ctxt->modrm >> 3) & 7;
+			if ((ctxt->modrm >> 6) == 3)
 				opcode = opcode.u.gdual->mod3[goffset];
 			else
 				opcode = opcode.u.gdual->mod012[goffset];
 			break;
 		case RMExt:
-			goffset = c->modrm & 7;
+			goffset = ctxt->modrm & 7;
 			opcode = opcode.u.group[goffset];
 			break;
 		case Prefix:
-			if (c->rep_prefix && op_prefix)
+			if (ctxt->rep_prefix && op_prefix)
 				return X86EMUL_UNHANDLEABLE;
-			simd_prefix = op_prefix ? 0x66 : c->rep_prefix;
+			simd_prefix = op_prefix ? 0x66 : ctxt->rep_prefix;
 			switch (simd_prefix) {
 			case 0x00: opcode = opcode.u.gprefix->pfx_no; break;
 			case 0x66: opcode = opcode.u.gprefix->pfx_66; break;
@@ -3501,61 +3471,61 @@ done_prefixes:
 			return X86EMUL_UNHANDLEABLE;
 		}
 
-		c->d &= ~GroupMask;
-		c->d |= opcode.flags;
+		ctxt->d &= ~GroupMask;
+		ctxt->d |= opcode.flags;
 	}
 
-	c->execute = opcode.u.execute;
-	c->check_perm = opcode.check_perm;
-	c->intercept = opcode.intercept;
+	ctxt->execute = opcode.u.execute;
+	ctxt->check_perm = opcode.check_perm;
+	ctxt->intercept = opcode.intercept;
 
 	/* Unrecognised? */
-	if (c->d == 0 || (c->d & Undefined))
+	if (ctxt->d == 0 || (ctxt->d & Undefined))
 		return -1;
 
-	if (!(c->d & VendorSpecific) && ctxt->only_vendor_specific_insn)
+	if (!(ctxt->d & VendorSpecific) && ctxt->only_vendor_specific_insn)
 		return -1;
 
-	if (mode == X86EMUL_MODE_PROT64 && (c->d & Stack))
-		c->op_bytes = 8;
+	if (mode == X86EMUL_MODE_PROT64 && (ctxt->d & Stack))
+		ctxt->op_bytes = 8;
 
-	if (c->d & Op3264) {
+	if (ctxt->d & Op3264) {
 		if (mode == X86EMUL_MODE_PROT64)
-			c->op_bytes = 8;
+			ctxt->op_bytes = 8;
 		else
-			c->op_bytes = 4;
+			ctxt->op_bytes = 4;
 	}
 
-	if (c->d & Sse)
-		c->op_bytes = 16;
+	if (ctxt->d & Sse)
+		ctxt->op_bytes = 16;
 
 	/* ModRM and SIB bytes. */
-	if (c->d & ModRM) {
-		rc = decode_modrm(ctxt, ops, &memop);
-		if (!c->has_seg_override)
-			set_seg_override(c, c->modrm_seg);
-	} else if (c->d & MemAbs)
-		rc = decode_abs(ctxt, ops, &memop);
+	if (ctxt->d & ModRM) {
+		rc = decode_modrm(ctxt, &memop);
+		if (!ctxt->has_seg_override)
+			set_seg_override(ctxt, ctxt->modrm_seg);
+	} else if (ctxt->d & MemAbs)
+		rc = decode_abs(ctxt, &memop);
 	if (rc != X86EMUL_CONTINUE)
 		goto done;
 
-	if (!c->has_seg_override)
-		set_seg_override(c, VCPU_SREG_DS);
+	if (!ctxt->has_seg_override)
+		set_seg_override(ctxt, VCPU_SREG_DS);
 
-	memop.addr.mem.seg = seg_override(ctxt, c);
+	memop.addr.mem.seg = seg_override(ctxt);
 
-	if (memop.type == OP_MEM && c->ad_bytes != 8)
+	if (memop.type == OP_MEM && ctxt->ad_bytes != 8)
 		memop.addr.mem.ea = (u32)memop.addr.mem.ea;
 
 	/*
 	 * Decode and fetch the source operand: register, memory
 	 * or immediate.
 	 */
-	switch (c->d & SrcMask) {
+	switch (ctxt->d & SrcMask) {
 	case SrcNone:
 		break;
 	case SrcReg:
-		decode_register_operand(ctxt, &c->src, c, 0);
+		decode_register_operand(ctxt, &ctxt->src, 0);
 		break;
 	case SrcMem16:
 		memop.bytes = 2;
@@ -3564,60 +3534,60 @@ done_prefixes:
 		memop.bytes = 4;
 		goto srcmem_common;
 	case SrcMem:
-		memop.bytes = (c->d & ByteOp) ? 1 :
-							   c->op_bytes;
+		memop.bytes = (ctxt->d & ByteOp) ? 1 :
+							   ctxt->op_bytes;
 	srcmem_common:
-		c->src = memop;
-		memopp = &c->src;
+		ctxt->src = memop;
+		memopp = &ctxt->src;
 		break;
 	case SrcImmU16:
-		rc = decode_imm(ctxt, &c->src, 2, false);
+		rc = decode_imm(ctxt, &ctxt->src, 2, false);
 		break;
 	case SrcImm:
-		rc = decode_imm(ctxt, &c->src, imm_size(c), true);
+		rc = decode_imm(ctxt, &ctxt->src, imm_size(ctxt), true);
 		break;
 	case SrcImmU:
-		rc = decode_imm(ctxt, &c->src, imm_size(c), false);
+		rc = decode_imm(ctxt, &ctxt->src, imm_size(ctxt), false);
 		break;
 	case SrcImmByte:
-		rc = decode_imm(ctxt, &c->src, 1, true);
+		rc = decode_imm(ctxt, &ctxt->src, 1, true);
 		break;
 	case SrcImmUByte:
-		rc = decode_imm(ctxt, &c->src, 1, false);
+		rc = decode_imm(ctxt, &ctxt->src, 1, false);
 		break;
 	case SrcAcc:
-		c->src.type = OP_REG;
-		c->src.bytes = (c->d & ByteOp) ? 1 : c->op_bytes;
-		c->src.addr.reg = &c->regs[VCPU_REGS_RAX];
-		fetch_register_operand(&c->src);
+		ctxt->src.type = OP_REG;
+		ctxt->src.bytes = (ctxt->d & ByteOp) ? 1 : ctxt->op_bytes;
+		ctxt->src.addr.reg = &ctxt->regs[VCPU_REGS_RAX];
+		fetch_register_operand(&ctxt->src);
 		break;
 	case SrcOne:
-		c->src.bytes = 1;
-		c->src.val = 1;
+		ctxt->src.bytes = 1;
+		ctxt->src.val = 1;
 		break;
 	case SrcSI:
-		c->src.type = OP_MEM;
-		c->src.bytes = (c->d & ByteOp) ? 1 : c->op_bytes;
-		c->src.addr.mem.ea =
-			register_address(c, c->regs[VCPU_REGS_RSI]);
-		c->src.addr.mem.seg = seg_override(ctxt, c);
-		c->src.val = 0;
+		ctxt->src.type = OP_MEM;
+		ctxt->src.bytes = (ctxt->d & ByteOp) ? 1 : ctxt->op_bytes;
+		ctxt->src.addr.mem.ea =
+			register_address(ctxt, ctxt->regs[VCPU_REGS_RSI]);
+		ctxt->src.addr.mem.seg = seg_override(ctxt);
+		ctxt->src.val = 0;
 		break;
 	case SrcImmFAddr:
-		c->src.type = OP_IMM;
-		c->src.addr.mem.ea = c->eip;
-		c->src.bytes = c->op_bytes + 2;
-		insn_fetch_arr(c->src.valptr, c->src.bytes, c->eip);
+		ctxt->src.type = OP_IMM;
+		ctxt->src.addr.mem.ea = ctxt->_eip;
+		ctxt->src.bytes = ctxt->op_bytes + 2;
+		insn_fetch_arr(ctxt->src.valptr, ctxt->src.bytes, ctxt->_eip);
 		break;
 	case SrcMemFAddr:
-		memop.bytes = c->op_bytes + 2;
+		memop.bytes = ctxt->op_bytes + 2;
 		goto srcmem_common;
 		break;
 	case SrcDX:
-		c->src.type = OP_REG;
-		c->src.bytes = 2;
-		c->src.addr.reg = &c->regs[VCPU_REGS_RDX];
-		fetch_register_operand(&c->src);
+		ctxt->src.type = OP_REG;
+		ctxt->src.bytes = 2;
+		ctxt->src.addr.reg = &ctxt->regs[VCPU_REGS_RDX];
+		fetch_register_operand(&ctxt->src);
 		break;
 	}
 
@@ -3628,22 +3598,22 @@ done_prefixes:
 	 * Decode and fetch the second source operand: register, memory
 	 * or immediate.
 	 */
-	switch (c->d & Src2Mask) {
+	switch (ctxt->d & Src2Mask) {
 	case Src2None:
 		break;
 	case Src2CL:
-		c->src2.bytes = 1;
-		c->src2.val = c->regs[VCPU_REGS_RCX] & 0x8;
+		ctxt->src2.bytes = 1;
+		ctxt->src2.val = ctxt->regs[VCPU_REGS_RCX] & 0x8;
 		break;
 	case Src2ImmByte:
-		rc = decode_imm(ctxt, &c->src2, 1, true);
+		rc = decode_imm(ctxt, &ctxt->src2, 1, true);
 		break;
 	case Src2One:
-		c->src2.bytes = 1;
-		c->src2.val = 1;
+		ctxt->src2.bytes = 1;
+		ctxt->src2.val = 1;
 		break;
 	case Src2Imm:
-		rc = decode_imm(ctxt, &c->src2, imm_size(c), true);
+		rc = decode_imm(ctxt, &ctxt->src2, imm_size(ctxt), true);
 		break;
 	}
 
@@ -3651,68 +3621,66 @@ done_prefixes:
 		goto done;
 
 	/* Decode and fetch the destination operand: register or memory. */
-	switch (c->d & DstMask) {
+	switch (ctxt->d & DstMask) {
 	case DstReg:
-		decode_register_operand(ctxt, &c->dst, c,
-			 c->twobyte && (c->b == 0xb6 || c->b == 0xb7));
+		decode_register_operand(ctxt, &ctxt->dst,
+			 ctxt->twobyte && (ctxt->b == 0xb6 || ctxt->b == 0xb7));
 		break;
 	case DstImmUByte:
-		c->dst.type = OP_IMM;
-		c->dst.addr.mem.ea = c->eip;
-		c->dst.bytes = 1;
-		c->dst.val = insn_fetch(u8, 1, c->eip);
+		ctxt->dst.type = OP_IMM;
+		ctxt->dst.addr.mem.ea = ctxt->_eip;
+		ctxt->dst.bytes = 1;
+		ctxt->dst.val = insn_fetch(u8, 1, ctxt->_eip);
 		break;
 	case DstMem:
 	case DstMem64:
-		c->dst = memop;
-		memopp = &c->dst;
-		if ((c->d & DstMask) == DstMem64)
-			c->dst.bytes = 8;
+		ctxt->dst = memop;
+		memopp = &ctxt->dst;
+		if ((ctxt->d & DstMask) == DstMem64)
+			ctxt->dst.bytes = 8;
 		else
-			c->dst.bytes = (c->d & ByteOp) ? 1 : c->op_bytes;
-		if (c->d & BitOp)
-			fetch_bit_operand(c);
-		c->dst.orig_val = c->dst.val;
+			ctxt->dst.bytes = (ctxt->d & ByteOp) ? 1 : ctxt->op_bytes;
+		if (ctxt->d & BitOp)
+			fetch_bit_operand(ctxt);
+		ctxt->dst.orig_val = ctxt->dst.val;
 		break;
 	case DstAcc:
-		c->dst.type = OP_REG;
-		c->dst.bytes = (c->d & ByteOp) ? 1 : c->op_bytes;
-		c->dst.addr.reg = &c->regs[VCPU_REGS_RAX];
-		fetch_register_operand(&c->dst);
-		c->dst.orig_val = c->dst.val;
+		ctxt->dst.type = OP_REG;
+		ctxt->dst.bytes = (ctxt->d & ByteOp) ? 1 : ctxt->op_bytes;
+		ctxt->dst.addr.reg = &ctxt->regs[VCPU_REGS_RAX];
+		fetch_register_operand(&ctxt->dst);
+		ctxt->dst.orig_val = ctxt->dst.val;
 		break;
 	case DstDI:
-		c->dst.type = OP_MEM;
-		c->dst.bytes = (c->d & ByteOp) ? 1 : c->op_bytes;
-		c->dst.addr.mem.ea =
-			register_address(c, c->regs[VCPU_REGS_RDI]);
-		c->dst.addr.mem.seg = VCPU_SREG_ES;
-		c->dst.val = 0;
+		ctxt->dst.type = OP_MEM;
+		ctxt->dst.bytes = (ctxt->d & ByteOp) ? 1 : ctxt->op_bytes;
+		ctxt->dst.addr.mem.ea =
+			register_address(ctxt, ctxt->regs[VCPU_REGS_RDI]);
+		ctxt->dst.addr.mem.seg = VCPU_SREG_ES;
+		ctxt->dst.val = 0;
 		break;
 	case DstDX:
-		c->dst.type = OP_REG;
-		c->dst.bytes = 2;
-		c->dst.addr.reg = &c->regs[VCPU_REGS_RDX];
-		fetch_register_operand(&c->dst);
+		ctxt->dst.type = OP_REG;
+		ctxt->dst.bytes = 2;
+		ctxt->dst.addr.reg = &ctxt->regs[VCPU_REGS_RDX];
+		fetch_register_operand(&ctxt->dst);
 		break;
 	case ImplicitOps:
 		/* Special instructions do their own operand decoding. */
 	default:
-		c->dst.type = OP_NONE; /* Disable writeback. */
+		ctxt->dst.type = OP_NONE; /* Disable writeback. */
 		break;
 	}
 
 done:
-	if (memopp && memopp->type == OP_MEM && c->rip_relative)
-		memopp->addr.mem.ea += c->eip;
+	if (memopp && memopp->type == OP_MEM && ctxt->rip_relative)
+		memopp->addr.mem.ea += ctxt->_eip;
 
 	return (rc == X86EMUL_UNHANDLEABLE) ? EMULATION_FAILED : EMULATION_OK;
 }
 
 static bool string_insn_completed(struct x86_emulate_ctxt *ctxt)
 {
-	struct decode_cache *c = &ctxt->decode;
-
 	/* The second termination condition only applies for REPE
 	 * and REPNE. Test if the repeat string operation prefix is
 	 * REPE/REPZ or REPNE/REPNZ and if it's the case it tests the
@@ -3720,304 +3688,232 @@ static bool string_insn_completed(struct x86_emulate_ctxt *ctxt)
 	 * 	- if REPE/REPZ and ZF = 0 then done
 	 * 	- if REPNE/REPNZ and ZF = 1 then done
 	 */
-	if (((c->b == 0xa6) || (c->b == 0xa7) ||
-	     (c->b == 0xae) || (c->b == 0xaf))
-	    && (((c->rep_prefix == REPE_PREFIX) &&
+	if (((ctxt->b == 0xa6) || (ctxt->b == 0xa7) ||
+	     (ctxt->b == 0xae) || (ctxt->b == 0xaf))
+	    && (((ctxt->rep_prefix == REPE_PREFIX) &&
 		 ((ctxt->eflags & EFLG_ZF) == 0))
-		|| ((c->rep_prefix == REPNE_PREFIX) &&
+		|| ((ctxt->rep_prefix == REPNE_PREFIX) &&
 		    ((ctxt->eflags & EFLG_ZF) == EFLG_ZF))))
 		return true;
 
 	return false;
 }
 
-int
-x86_emulate_insn(struct x86_emulate_ctxt *ctxt)
+int x86_emulate_insn(struct x86_emulate_ctxt *ctxt)
 {
 	struct x86_emulate_ops *ops = ctxt->ops;
 	u64 msr_data;
-	struct decode_cache *c = &ctxt->decode;
 	int rc = X86EMUL_CONTINUE;
-	int saved_dst_type = c->dst.type;
-	int irq; /* Used for int 3, int, and into */
+	int saved_dst_type = ctxt->dst.type;
 
-	ctxt->decode.mem_read.pos = 0;
+	ctxt->mem_read.pos = 0;
 
-	if (ctxt->mode == X86EMUL_MODE_PROT64 && (c->d & No64)) {
+	if (ctxt->mode == X86EMUL_MODE_PROT64 && (ctxt->d & No64)) {
 		rc = emulate_ud(ctxt);
 		goto done;
 	}
 
 	/* LOCK prefix is allowed only with some instructions */
-	if (c->lock_prefix && (!(c->d & Lock) || c->dst.type != OP_MEM)) {
+	if (ctxt->lock_prefix && (!(ctxt->d & Lock) || ctxt->dst.type != OP_MEM)) {
 		rc = emulate_ud(ctxt);
 		goto done;
 	}
 
-	if ((c->d & SrcMask) == SrcMemFAddr && c->src.type != OP_MEM) {
+	if ((ctxt->d & SrcMask) == SrcMemFAddr && ctxt->src.type != OP_MEM) {
 		rc = emulate_ud(ctxt);
 		goto done;
 	}
 
-	if ((c->d & Sse)
+	if ((ctxt->d & Sse)
 	    && ((ops->get_cr(ctxt, 0) & X86_CR0_EM)
 		|| !(ops->get_cr(ctxt, 4) & X86_CR4_OSFXSR))) {
 		rc = emulate_ud(ctxt);
 		goto done;
 	}
 
-	if ((c->d & Sse) && (ops->get_cr(ctxt, 0) & X86_CR0_TS)) {
+	if ((ctxt->d & Sse) && (ops->get_cr(ctxt, 0) & X86_CR0_TS)) {
 		rc = emulate_nm(ctxt);
 		goto done;
 	}
 
-	if (unlikely(ctxt->guest_mode) && c->intercept) {
-		rc = emulator_check_intercept(ctxt, c->intercept,
+	if (unlikely(ctxt->guest_mode) && ctxt->intercept) {
+		rc = emulator_check_intercept(ctxt, ctxt->intercept,
 					      X86_ICPT_PRE_EXCEPT);
 		if (rc != X86EMUL_CONTINUE)
 			goto done;
 	}
 
 	/* Privileged instruction can be executed only in CPL=0 */
-	if ((c->d & Priv) && ops->cpl(ctxt)) {
+	if ((ctxt->d & Priv) && ops->cpl(ctxt)) {
 		rc = emulate_gp(ctxt, 0);
 		goto done;
 	}
 
 	/* Instruction can only be executed in protected mode */
-	if ((c->d & Prot) && !(ctxt->mode & X86EMUL_MODE_PROT)) {
+	if ((ctxt->d & Prot) && !(ctxt->mode & X86EMUL_MODE_PROT)) {
 		rc = emulate_ud(ctxt);
 		goto done;
 	}
 
 	/* Do instruction specific permission checks */
-	if (c->check_perm) {
-		rc = c->check_perm(ctxt);
+	if (ctxt->check_perm) {
+		rc = ctxt->check_perm(ctxt);
 		if (rc != X86EMUL_CONTINUE)
 			goto done;
 	}
 
-	if (unlikely(ctxt->guest_mode) && c->intercept) {
-		rc = emulator_check_intercept(ctxt, c->intercept,
+	if (unlikely(ctxt->guest_mode) && ctxt->intercept) {
+		rc = emulator_check_intercept(ctxt, ctxt->intercept,
 					      X86_ICPT_POST_EXCEPT);
 		if (rc != X86EMUL_CONTINUE)
 			goto done;
 	}
 
-	if (c->rep_prefix && (c->d & String)) {
+	if (ctxt->rep_prefix && (ctxt->d & String)) {
 		/* All REP prefixes have the same first termination condition */
-		if (address_mask(c, c->regs[VCPU_REGS_RCX]) == 0) {
-			ctxt->eip = c->eip;
+		if (address_mask(ctxt, ctxt->regs[VCPU_REGS_RCX]) == 0) {
+			ctxt->eip = ctxt->_eip;
 			goto done;
 		}
 	}
 
-	if ((c->src.type == OP_MEM) && !(c->d & NoAccess)) {
-		rc = segmented_read(ctxt, c->src.addr.mem,
-				    c->src.valptr, c->src.bytes);
+	if ((ctxt->src.type == OP_MEM) && !(ctxt->d & NoAccess)) {
+		rc = segmented_read(ctxt, ctxt->src.addr.mem,
+				    ctxt->src.valptr, ctxt->src.bytes);
 		if (rc != X86EMUL_CONTINUE)
 			goto done;
-		c->src.orig_val64 = c->src.val64;
+		ctxt->src.orig_val64 = ctxt->src.val64;
 	}
 
-	if (c->src2.type == OP_MEM) {
-		rc = segmented_read(ctxt, c->src2.addr.mem,
-				    &c->src2.val, c->src2.bytes);
+	if (ctxt->src2.type == OP_MEM) {
+		rc = segmented_read(ctxt, ctxt->src2.addr.mem,
+				    &ctxt->src2.val, ctxt->src2.bytes);
 		if (rc != X86EMUL_CONTINUE)
 			goto done;
 	}
 
-	if ((c->d & DstMask) == ImplicitOps)
+	if ((ctxt->d & DstMask) == ImplicitOps)
 		goto special_insn;
 
 
-	if ((c->dst.type == OP_MEM) && !(c->d & Mov)) {
+	if ((ctxt->dst.type == OP_MEM) && !(ctxt->d & Mov)) {
 		/* optimisation - avoid slow emulated read if Mov */
-		rc = segmented_read(ctxt, c->dst.addr.mem,
-				   &c->dst.val, c->dst.bytes);
+		rc = segmented_read(ctxt, ctxt->dst.addr.mem,
+				   &ctxt->dst.val, ctxt->dst.bytes);
 		if (rc != X86EMUL_CONTINUE)
 			goto done;
 	}
-	c->dst.orig_val = c->dst.val;
+	ctxt->dst.orig_val = ctxt->dst.val;
 
 special_insn:
 
-	if (unlikely(ctxt->guest_mode) && c->intercept) {
-		rc = emulator_check_intercept(ctxt, c->intercept,
+	if (unlikely(ctxt->guest_mode) && ctxt->intercept) {
+		rc = emulator_check_intercept(ctxt, ctxt->intercept,
 					      X86_ICPT_POST_MEMACCESS);
 		if (rc != X86EMUL_CONTINUE)
 			goto done;
 	}
 
-	if (c->execute) {
-		rc = c->execute(ctxt);
+	if (ctxt->execute) {
+		rc = ctxt->execute(ctxt);
 		if (rc != X86EMUL_CONTINUE)
 			goto done;
 		goto writeback;
 	}
 
-	if (c->twobyte)
+	if (ctxt->twobyte)
 		goto twobyte_insn;
 
-	switch (c->b) {
+	switch (ctxt->b) {
 	case 0x06:		/* push es */
-		rc = emulate_push_sreg(ctxt, ops, VCPU_SREG_ES);
+		rc = emulate_push_sreg(ctxt, VCPU_SREG_ES);
 		break;
 	case 0x07:		/* pop es */
-		rc = emulate_pop_sreg(ctxt, ops, VCPU_SREG_ES);
+		rc = emulate_pop_sreg(ctxt, VCPU_SREG_ES);
 		break;
 	case 0x0e:		/* push cs */
-		rc = emulate_push_sreg(ctxt, ops, VCPU_SREG_CS);
+		rc = emulate_push_sreg(ctxt, VCPU_SREG_CS);
 		break;
 	case 0x16:		/* push ss */
-		rc = emulate_push_sreg(ctxt, ops, VCPU_SREG_SS);
+		rc = emulate_push_sreg(ctxt, VCPU_SREG_SS);
 		break;
 	case 0x17:		/* pop ss */
-		rc = emulate_pop_sreg(ctxt, ops, VCPU_SREG_SS);
+		rc = emulate_pop_sreg(ctxt, VCPU_SREG_SS);
 		break;
 	case 0x1e:		/* push ds */
-		rc = emulate_push_sreg(ctxt, ops, VCPU_SREG_DS);
+		rc = emulate_push_sreg(ctxt, VCPU_SREG_DS);
 		break;
 	case 0x1f:		/* pop ds */
-		rc = emulate_pop_sreg(ctxt, ops, VCPU_SREG_DS);
+		rc = emulate_pop_sreg(ctxt, VCPU_SREG_DS);
 		break;
 	case 0x40 ... 0x47: /* inc r16/r32 */
-		emulate_1op("inc", c->dst, ctxt->eflags);
+		emulate_1op("inc", ctxt->dst, ctxt->eflags);
 		break;
 	case 0x48 ... 0x4f: /* dec r16/r32 */
-		emulate_1op("dec", c->dst, ctxt->eflags);
+		emulate_1op("dec", ctxt->dst, ctxt->eflags);
 		break;
 	case 0x63:		/* movsxd */
 		if (ctxt->mode != X86EMUL_MODE_PROT64)
 			goto cannot_emulate;
-		c->dst.val = (s32) c->src.val;
+		ctxt->dst.val = (s32) ctxt->src.val;
 		break;
 	case 0x6c:		/* insb */
 	case 0x6d:		/* insw/insd */
-		c->src.val = c->regs[VCPU_REGS_RDX];
+		ctxt->src.val = ctxt->regs[VCPU_REGS_RDX];
 		goto do_io_in;
 	case 0x6e:		/* outsb */
 	case 0x6f:		/* outsw/outsd */
-		c->dst.val = c->regs[VCPU_REGS_RDX];
+		ctxt->dst.val = ctxt->regs[VCPU_REGS_RDX];
 		goto do_io_out;
 		break;
 	case 0x70 ... 0x7f: /* jcc (short) */
-		if (test_cc(c->b, ctxt->eflags))
-			jmp_rel(c, c->src.val);
-		break;
-	case 0x84 ... 0x85:
-	test:
-		emulate_2op_SrcV("test", c->src, c->dst, ctxt->eflags);
-		break;
-	case 0x86 ... 0x87:	/* xchg */
-	xchg:
-		/* Write back the register source. */
-		c->src.val = c->dst.val;
-		write_register_operand(&c->src);
-		/*
-		 * Write back the memory destination with implicit LOCK
-		 * prefix.
-		 */
-		c->dst.val = c->src.orig_val;
-		c->lock_prefix = 1;
-		break;
-	case 0x8c:  /* mov r/m, sreg */
-		if (c->modrm_reg > VCPU_SREG_GS) {
-			rc = emulate_ud(ctxt);
-			goto done;
-		}
-		c->dst.val = get_segment_selector(ctxt, c->modrm_reg);
+		if (test_cc(ctxt->b, ctxt->eflags))
+			jmp_rel(ctxt, ctxt->src.val);
 		break;
 	case 0x8d: /* lea r16/r32, m */
-		c->dst.val = c->src.addr.mem.ea;
+		ctxt->dst.val = ctxt->src.addr.mem.ea;
 		break;
-	case 0x8e: { /* mov seg, r/m16 */
-		uint16_t sel;
-
-		sel = c->src.val;
-
-		if (c->modrm_reg == VCPU_SREG_CS ||
-		    c->modrm_reg > VCPU_SREG_GS) {
-			rc = emulate_ud(ctxt);
-			goto done;
-		}
-
-		if (c->modrm_reg == VCPU_SREG_SS)
-			ctxt->interruptibility = KVM_X86_SHADOW_INT_MOV_SS;
-
-		rc = load_segment_descriptor(ctxt, ops, sel, c->modrm_reg);
-
-		c->dst.type = OP_NONE;  /* Disable writeback. */
-		break;
-	}
 	case 0x8f:		/* pop (sole member of Grp1a) */
 		rc = em_grp1a(ctxt);
 		break;
 	case 0x90 ... 0x97: /* nop / xchg reg, rax */
-		if (c->dst.addr.reg == &c->regs[VCPU_REGS_RAX])
+		if (ctxt->dst.addr.reg == &ctxt->regs[VCPU_REGS_RAX])
 			break;
-		goto xchg;
+		rc = em_xchg(ctxt);
+		break;
 	case 0x98: /* cbw/cwde/cdqe */
-		switch (c->op_bytes) {
-		case 2: c->dst.val = (s8)c->dst.val; break;
-		case 4: c->dst.val = (s16)c->dst.val; break;
-		case 8: c->dst.val = (s32)c->dst.val; break;
+		switch (ctxt->op_bytes) {
+		case 2: ctxt->dst.val = (s8)ctxt->dst.val; break;
+		case 4: ctxt->dst.val = (s16)ctxt->dst.val; break;
+		case 8: ctxt->dst.val = (s32)ctxt->dst.val; break;
 		}
 		break;
-	case 0xa8 ... 0xa9:	/* test ax, imm */
-		goto test;
 	case 0xc0 ... 0xc1:
 		rc = em_grp2(ctxt);
 		break;
-	case 0xc3: /* ret */
-		c->dst.type = OP_REG;
-		c->dst.addr.reg = &c->eip;
-		c->dst.bytes = c->op_bytes;
-		rc = em_pop(ctxt);
-		break;
 	case 0xc4:		/* les */
-		rc = emulate_load_segment(ctxt, ops, VCPU_SREG_ES);
+		rc = emulate_load_segment(ctxt, VCPU_SREG_ES);
 		break;
 	case 0xc5:		/* lds */
-		rc = emulate_load_segment(ctxt, ops, VCPU_SREG_DS);
-		break;
-	case 0xcb:		/* ret far */
-		rc = emulate_ret_far(ctxt, ops);
+		rc = emulate_load_segment(ctxt, VCPU_SREG_DS);
 		break;
 	case 0xcc:		/* int3 */
-		irq = 3;
-		goto do_interrupt;
+		rc = emulate_int(ctxt, 3);
+		break;
 	case 0xcd:		/* int n */
-		irq = c->src.val;
-	do_interrupt:
-		rc = emulate_int(ctxt, ops, irq);
+		rc = emulate_int(ctxt, ctxt->src.val);
 		break;
 	case 0xce:		/* into */
-		if (ctxt->eflags & EFLG_OF) {
-			irq = 4;
-			goto do_interrupt;
-		}
-		break;
-	case 0xcf:		/* iret */
-		rc = emulate_iret(ctxt, ops);
+		if (ctxt->eflags & EFLG_OF)
+			rc = emulate_int(ctxt, 4);
 		break;
 	case 0xd0 ... 0xd1:	/* Grp2 */
 		rc = em_grp2(ctxt);
 		break;
 	case 0xd2 ... 0xd3:	/* Grp2 */
-		c->src.val = c->regs[VCPU_REGS_RCX];
+		ctxt->src.val = ctxt->regs[VCPU_REGS_RCX];
 		rc = em_grp2(ctxt);
 		break;
-	case 0xe0 ... 0xe2:	/* loop/loopz/loopnz */
-		register_address_increment(c, &c->regs[VCPU_REGS_RCX], -1);
-		if (address_mask(c, c->regs[VCPU_REGS_RCX]) != 0 &&
-		    (c->b == 0xe2 || test_cc(c->b ^ 0x5, ctxt->eflags)))
-			jmp_rel(c, c->src.val);
-		break;
-	case 0xe3:	/* jcxz/jecxz/jrcxz */
-		if (address_mask(c, c->regs[VCPU_REGS_RCX]) == 0)
-			jmp_rel(c, c->src.val);
-		break;
 	case 0xe4: 	/* inb */
 	case 0xe5: 	/* in */
 		goto do_io_in;
@@ -4025,35 +3921,30 @@ special_insn:
 	case 0xe7: /* out */
 		goto do_io_out;
 	case 0xe8: /* call (near) */ {
-		long int rel = c->src.val;
-		c->src.val = (unsigned long) c->eip;
-		jmp_rel(c, rel);
+		long int rel = ctxt->src.val;
+		ctxt->src.val = (unsigned long) ctxt->_eip;
+		jmp_rel(ctxt, rel);
 		rc = em_push(ctxt);
 		break;
 	}
 	case 0xe9: /* jmp rel */
-		goto jmp;
-	case 0xea: /* jmp far */
-		rc = em_jmp_far(ctxt);
-		break;
-	case 0xeb:
-	      jmp:		/* jmp rel short */
-		jmp_rel(c, c->src.val);
-		c->dst.type = OP_NONE; /* Disable writeback. */
+	case 0xeb: /* jmp rel short */
+		jmp_rel(ctxt, ctxt->src.val);
+		ctxt->dst.type = OP_NONE; /* Disable writeback. */
 		break;
 	case 0xec: /* in al,dx */
 	case 0xed: /* in (e/r)ax,dx */
 	do_io_in:
-		if (!pio_in_emulated(ctxt, ops, c->dst.bytes, c->src.val,
-				     &c->dst.val))
+		if (!pio_in_emulated(ctxt, ctxt->dst.bytes, ctxt->src.val,
+				     &ctxt->dst.val))
 			goto done; /* IO is needed */
 		break;
 	case 0xee: /* out dx,al */
 	case 0xef: /* out dx,(e/r)ax */
 	do_io_out:
-		ops->pio_out_emulated(ctxt, c->src.bytes, c->dst.val,
-				      &c->src.val, 1);
-		c->dst.type = OP_NONE;	/* Disable writeback. */
+		ops->pio_out_emulated(ctxt, ctxt->src.bytes, ctxt->dst.val,
+				      &ctxt->src.val, 1);
+		ctxt->dst.type = OP_NONE;	/* Disable writeback. */
 		break;
 	case 0xf4:              /* hlt */
 		ctxt->ops->halt(ctxt);
@@ -4071,22 +3962,6 @@ special_insn:
 	case 0xf9: /* stc */
 		ctxt->eflags |= EFLG_CF;
 		break;
-	case 0xfa: /* cli */
-		if (emulator_bad_iopl(ctxt, ops)) {
-			rc = emulate_gp(ctxt, 0);
-			goto done;
-		} else
-			ctxt->eflags &= ~X86_EFLAGS_IF;
-		break;
-	case 0xfb: /* sti */
-		if (emulator_bad_iopl(ctxt, ops)) {
-			rc = emulate_gp(ctxt, 0);
-			goto done;
-		} else {
-			ctxt->interruptibility = KVM_X86_SHADOW_INT_STI;
-			ctxt->eflags |= X86_EFLAGS_IF;
-		}
-		break;
 	case 0xfc: /* cld */
 		ctxt->eflags &= ~EFLG_DF;
 		break;
@@ -4115,40 +3990,40 @@ writeback:
 	 * restore dst type in case the decoding will be reused
 	 * (happens for string instruction )
 	 */
-	c->dst.type = saved_dst_type;
+	ctxt->dst.type = saved_dst_type;
 
-	if ((c->d & SrcMask) == SrcSI)
-		string_addr_inc(ctxt, seg_override(ctxt, c),
-				VCPU_REGS_RSI, &c->src);
+	if ((ctxt->d & SrcMask) == SrcSI)
+		string_addr_inc(ctxt, seg_override(ctxt),
+				VCPU_REGS_RSI, &ctxt->src);
 
-	if ((c->d & DstMask) == DstDI)
+	if ((ctxt->d & DstMask) == DstDI)
 		string_addr_inc(ctxt, VCPU_SREG_ES, VCPU_REGS_RDI,
-				&c->dst);
+				&ctxt->dst);
 
-	if (c->rep_prefix && (c->d & String)) {
-		struct read_cache *r = &ctxt->decode.io_read;
-		register_address_increment(c, &c->regs[VCPU_REGS_RCX], -1);
+	if (ctxt->rep_prefix && (ctxt->d & String)) {
+		struct read_cache *r = &ctxt->io_read;
+		register_address_increment(ctxt, &ctxt->regs[VCPU_REGS_RCX], -1);
 
 		if (!string_insn_completed(ctxt)) {
 			/*
 			 * Re-enter guest when pio read ahead buffer is empty
 			 * or, if it is not used, after each 1024 iteration.
 			 */
-			if ((r->end != 0 || c->regs[VCPU_REGS_RCX] & 0x3ff) &&
+			if ((r->end != 0 || ctxt->regs[VCPU_REGS_RCX] & 0x3ff) &&
 			    (r->end == 0 || r->end != r->pos)) {
 				/*
 				 * Reset read cache. Usually happens before
 				 * decode, but since instruction is restarted
 				 * we have to do it here.
 				 */
-				ctxt->decode.mem_read.end = 0;
+				ctxt->mem_read.end = 0;
 				return EMULATION_RESTART;
 			}
 			goto done; /* skip rip writeback */
 		}
 	}
 
-	ctxt->eip = c->eip;
+	ctxt->eip = ctxt->_eip;
 
 done:
 	if (rc == X86EMUL_PROPAGATE_FAULT)
@@ -4159,13 +4034,7 @@ done:
 	return (rc == X86EMUL_UNHANDLEABLE) ? EMULATION_FAILED : EMULATION_OK;
 
 twobyte_insn:
-	switch (c->b) {
-	case 0x05: 		/* syscall */
-		rc = emulate_syscall(ctxt, ops);
-		break;
-	case 0x06:
-		rc = em_clts(ctxt);
-		break;
+	switch (ctxt->b) {
 	case 0x09:		/* wbinvd */
 		(ctxt->ops->wbinvd)(ctxt);
 		break;
@@ -4174,21 +4043,21 @@ twobyte_insn:
 	case 0x18:		/* Grp16 (prefetch/nop) */
 		break;
 	case 0x20: /* mov cr, reg */
-		c->dst.val = ops->get_cr(ctxt, c->modrm_reg);
+		ctxt->dst.val = ops->get_cr(ctxt, ctxt->modrm_reg);
 		break;
 	case 0x21: /* mov from dr to reg */
-		ops->get_dr(ctxt, c->modrm_reg, &c->dst.val);
+		ops->get_dr(ctxt, ctxt->modrm_reg, &ctxt->dst.val);
 		break;
 	case 0x22: /* mov reg, cr */
-		if (ops->set_cr(ctxt, c->modrm_reg, c->src.val)) {
+		if (ops->set_cr(ctxt, ctxt->modrm_reg, ctxt->src.val)) {
 			emulate_gp(ctxt, 0);
 			rc = X86EMUL_PROPAGATE_FAULT;
 			goto done;
 		}
-		c->dst.type = OP_NONE;
+		ctxt->dst.type = OP_NONE;
 		break;
 	case 0x23: /* mov from reg to dr */
-		if (ops->set_dr(ctxt, c->modrm_reg, c->src.val &
+		if (ops->set_dr(ctxt, ctxt->modrm_reg, ctxt->src.val &
 				((ctxt->mode == X86EMUL_MODE_PROT64) ?
 				 ~0ULL : ~0U)) < 0) {
 			/* #UD condition is already handled by the code above */
@@ -4197,13 +4066,13 @@ twobyte_insn:
 			goto done;
 		}
 
-		c->dst.type = OP_NONE;	/* no writeback */
+		ctxt->dst.type = OP_NONE;	/* no writeback */
 		break;
 	case 0x30:
 		/* wrmsr */
-		msr_data = (u32)c->regs[VCPU_REGS_RAX]
-			| ((u64)c->regs[VCPU_REGS_RDX] << 32);
-		if (ops->set_msr(ctxt, c->regs[VCPU_REGS_RCX], msr_data)) {
+		msr_data = (u32)ctxt->regs[VCPU_REGS_RAX]
+			| ((u64)ctxt->regs[VCPU_REGS_RDX] << 32);
+		if (ops->set_msr(ctxt, ctxt->regs[VCPU_REGS_RCX], msr_data)) {
 			emulate_gp(ctxt, 0);
 			rc = X86EMUL_PROPAGATE_FAULT;
 			goto done;
@@ -4212,64 +4081,58 @@ twobyte_insn:
 		break;
 	case 0x32:
 		/* rdmsr */
-		if (ops->get_msr(ctxt, c->regs[VCPU_REGS_RCX], &msr_data)) {
+		if (ops->get_msr(ctxt, ctxt->regs[VCPU_REGS_RCX], &msr_data)) {
 			emulate_gp(ctxt, 0);
 			rc = X86EMUL_PROPAGATE_FAULT;
 			goto done;
 		} else {
-			c->regs[VCPU_REGS_RAX] = (u32)msr_data;
-			c->regs[VCPU_REGS_RDX] = msr_data >> 32;
+			ctxt->regs[VCPU_REGS_RAX] = (u32)msr_data;
+			ctxt->regs[VCPU_REGS_RDX] = msr_data >> 32;
 		}
 		rc = X86EMUL_CONTINUE;
 		break;
-	case 0x34:		/* sysenter */
-		rc = emulate_sysenter(ctxt, ops);
-		break;
-	case 0x35:		/* sysexit */
-		rc = emulate_sysexit(ctxt, ops);
-		break;
 	case 0x40 ... 0x4f:	/* cmov */
-		c->dst.val = c->dst.orig_val = c->src.val;
-		if (!test_cc(c->b, ctxt->eflags))
-			c->dst.type = OP_NONE; /* no writeback */
+		ctxt->dst.val = ctxt->dst.orig_val = ctxt->src.val;
+		if (!test_cc(ctxt->b, ctxt->eflags))
+			ctxt->dst.type = OP_NONE; /* no writeback */
 		break;
 	case 0x80 ... 0x8f: /* jnz rel, etc*/
-		if (test_cc(c->b, ctxt->eflags))
-			jmp_rel(c, c->src.val);
+		if (test_cc(ctxt->b, ctxt->eflags))
+			jmp_rel(ctxt, ctxt->src.val);
 		break;
 	case 0x90 ... 0x9f:     /* setcc r/m8 */
-		c->dst.val = test_cc(c->b, ctxt->eflags);
+		ctxt->dst.val = test_cc(ctxt->b, ctxt->eflags);
 		break;
 	case 0xa0:	  /* push fs */
-		rc = emulate_push_sreg(ctxt, ops, VCPU_SREG_FS);
+		rc = emulate_push_sreg(ctxt, VCPU_SREG_FS);
 		break;
 	case 0xa1:	 /* pop fs */
-		rc = emulate_pop_sreg(ctxt, ops, VCPU_SREG_FS);
+		rc = emulate_pop_sreg(ctxt, VCPU_SREG_FS);
 		break;
 	case 0xa3:
 	      bt:		/* bt */
-		c->dst.type = OP_NONE;
+		ctxt->dst.type = OP_NONE;
 		/* only subword offset */
-		c->src.val &= (c->dst.bytes << 3) - 1;
-		emulate_2op_SrcV_nobyte("bt", c->src, c->dst, ctxt->eflags);
+		ctxt->src.val &= (ctxt->dst.bytes << 3) - 1;
+		emulate_2op_SrcV_nobyte("bt", ctxt->src, ctxt->dst, ctxt->eflags);
 		break;
 	case 0xa4: /* shld imm8, r, r/m */
 	case 0xa5: /* shld cl, r, r/m */
-		emulate_2op_cl("shld", c->src2, c->src, c->dst, ctxt->eflags);
+		emulate_2op_cl("shld", ctxt->src2, ctxt->src, ctxt->dst, ctxt->eflags);
 		break;
 	case 0xa8:	/* push gs */
-		rc = emulate_push_sreg(ctxt, ops, VCPU_SREG_GS);
+		rc = emulate_push_sreg(ctxt, VCPU_SREG_GS);
 		break;
 	case 0xa9:	/* pop gs */
-		rc = emulate_pop_sreg(ctxt, ops, VCPU_SREG_GS);
+		rc = emulate_pop_sreg(ctxt, VCPU_SREG_GS);
 		break;
 	case 0xab:
 	      bts:		/* bts */
-		emulate_2op_SrcV_nobyte("bts", c->src, c->dst, ctxt->eflags);
+		emulate_2op_SrcV_nobyte("bts", ctxt->src, ctxt->dst, ctxt->eflags);
 		break;
 	case 0xac: /* shrd imm8, r, r/m */
 	case 0xad: /* shrd cl, r, r/m */
-		emulate_2op_cl("shrd", c->src2, c->src, c->dst, ctxt->eflags);
+		emulate_2op_cl("shrd", ctxt->src2, ctxt->src, ctxt->dst, ctxt->eflags);
 		break;
 	case 0xae:              /* clflush */
 		break;
@@ -4278,38 +4141,38 @@ twobyte_insn:
 		 * Save real source value, then compare EAX against
 		 * destination.
 		 */
-		c->src.orig_val = c->src.val;
-		c->src.val = c->regs[VCPU_REGS_RAX];
-		emulate_2op_SrcV("cmp", c->src, c->dst, ctxt->eflags);
+		ctxt->src.orig_val = ctxt->src.val;
+		ctxt->src.val = ctxt->regs[VCPU_REGS_RAX];
+		emulate_2op_SrcV("cmp", ctxt->src, ctxt->dst, ctxt->eflags);
 		if (ctxt->eflags & EFLG_ZF) {
 			/* Success: write back to memory. */
-			c->dst.val = c->src.orig_val;
+			ctxt->dst.val = ctxt->src.orig_val;
 		} else {
 			/* Failure: write the value we saw to EAX. */
-			c->dst.type = OP_REG;
-			c->dst.addr.reg = (unsigned long *)&c->regs[VCPU_REGS_RAX];
+			ctxt->dst.type = OP_REG;
+			ctxt->dst.addr.reg = (unsigned long *)&ctxt->regs[VCPU_REGS_RAX];
 		}
 		break;
 	case 0xb2:		/* lss */
-		rc = emulate_load_segment(ctxt, ops, VCPU_SREG_SS);
+		rc = emulate_load_segment(ctxt, VCPU_SREG_SS);
 		break;
 	case 0xb3:
 	      btr:		/* btr */
-		emulate_2op_SrcV_nobyte("btr", c->src, c->dst, ctxt->eflags);
+		emulate_2op_SrcV_nobyte("btr", ctxt->src, ctxt->dst, ctxt->eflags);
 		break;
 	case 0xb4:		/* lfs */
-		rc = emulate_load_segment(ctxt, ops, VCPU_SREG_FS);
+		rc = emulate_load_segment(ctxt, VCPU_SREG_FS);
 		break;
 	case 0xb5:		/* lgs */
-		rc = emulate_load_segment(ctxt, ops, VCPU_SREG_GS);
+		rc = emulate_load_segment(ctxt, VCPU_SREG_GS);
 		break;
 	case 0xb6 ... 0xb7:	/* movzx */
-		c->dst.bytes = c->op_bytes;
-		c->dst.val = (c->d & ByteOp) ? (u8) c->src.val
-						       : (u16) c->src.val;
+		ctxt->dst.bytes = ctxt->op_bytes;
+		ctxt->dst.val = (ctxt->d & ByteOp) ? (u8) ctxt->src.val
+						       : (u16) ctxt->src.val;
 		break;
 	case 0xba:		/* Grp8 */
-		switch (c->modrm_reg & 3) {
+		switch (ctxt->modrm_reg & 3) {
 		case 0:
 			goto bt;
 		case 1:
@@ -4322,47 +4185,47 @@ twobyte_insn:
 		break;
 	case 0xbb:
 	      btc:		/* btc */
-		emulate_2op_SrcV_nobyte("btc", c->src, c->dst, ctxt->eflags);
+		emulate_2op_SrcV_nobyte("btc", ctxt->src, ctxt->dst, ctxt->eflags);
 		break;
 	case 0xbc: {		/* bsf */
 		u8 zf;
 		__asm__ ("bsf %2, %0; setz %1"
-			 : "=r"(c->dst.val), "=q"(zf)
-			 : "r"(c->src.val));
+			 : "=r"(ctxt->dst.val), "=q"(zf)
+			 : "r"(ctxt->src.val));
 		ctxt->eflags &= ~X86_EFLAGS_ZF;
 		if (zf) {
 			ctxt->eflags |= X86_EFLAGS_ZF;
-			c->dst.type = OP_NONE;	/* Disable writeback. */
+			ctxt->dst.type = OP_NONE;	/* Disable writeback. */
 		}
 		break;
 	}
 	case 0xbd: {		/* bsr */
 		u8 zf;
 		__asm__ ("bsr %2, %0; setz %1"
-			 : "=r"(c->dst.val), "=q"(zf)
-			 : "r"(c->src.val));
+			 : "=r"(ctxt->dst.val), "=q"(zf)
+			 : "r"(ctxt->src.val));
 		ctxt->eflags &= ~X86_EFLAGS_ZF;
 		if (zf) {
 			ctxt->eflags |= X86_EFLAGS_ZF;
-			c->dst.type = OP_NONE;	/* Disable writeback. */
+			ctxt->dst.type = OP_NONE;	/* Disable writeback. */
 		}
 		break;
 	}
 	case 0xbe ... 0xbf:	/* movsx */
-		c->dst.bytes = c->op_bytes;
-		c->dst.val = (c->d & ByteOp) ? (s8) c->src.val :
-							(s16) c->src.val;
+		ctxt->dst.bytes = ctxt->op_bytes;
+		ctxt->dst.val = (ctxt->d & ByteOp) ? (s8) ctxt->src.val :
+							(s16) ctxt->src.val;
 		break;
 	case 0xc0 ... 0xc1:	/* xadd */
-		emulate_2op_SrcV("add", c->src, c->dst, ctxt->eflags);
+		emulate_2op_SrcV("add", ctxt->src, ctxt->dst, ctxt->eflags);
 		/* Write back the register source. */
-		c->src.val = c->dst.orig_val;
-		write_register_operand(&c->src);
+		ctxt->src.val = ctxt->dst.orig_val;
+		write_register_operand(&ctxt->src);
 		break;
 	case 0xc3:		/* movnti */
-		c->dst.bytes = c->op_bytes;
-		c->dst.val = (c->op_bytes == 4) ? (u32) c->src.val :
-							(u64) c->src.val;
+		ctxt->dst.bytes = ctxt->op_bytes;
+		ctxt->dst.val = (ctxt->op_bytes == 4) ? (u32) ctxt->src.val :
+							(u64) ctxt->src.val;
 		break;
 	case 0xc7:		/* Grp9 (cmpxchg8b) */
 		rc = em_grp9(ctxt);
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index aee38623b768..9335e1bf72ad 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -148,7 +148,7 @@ module_param(oos_shadow, bool, 0644);
 #define PT64_PERM_MASK (PT_PRESENT_MASK | PT_WRITABLE_MASK | PT_USER_MASK \
 			| PT64_NX_MASK)
 
-#define RMAP_EXT 4
+#define PTE_LIST_EXT 4
 
 #define ACC_EXEC_MASK    1
 #define ACC_WRITE_MASK   PT_WRITABLE_MASK
@@ -164,16 +164,16 @@ module_param(oos_shadow, bool, 0644);
 
 #define SHADOW_PT_INDEX(addr, level) PT64_INDEX(addr, level)
 
-struct kvm_rmap_desc {
-	u64 *sptes[RMAP_EXT];
-	struct kvm_rmap_desc *more;
+struct pte_list_desc {
+	u64 *sptes[PTE_LIST_EXT];
+	struct pte_list_desc *more;
 };
 
 struct kvm_shadow_walk_iterator {
 	u64 addr;
 	hpa_t shadow_addr;
-	int level;
 	u64 *sptep;
+	int level;
 	unsigned index;
 };
 
@@ -182,32 +182,68 @@ struct kvm_shadow_walk_iterator {
 	     shadow_walk_okay(&(_walker));			\
 	     shadow_walk_next(&(_walker)))
 
-typedef void (*mmu_parent_walk_fn) (struct kvm_mmu_page *sp, u64 *spte);
+#define for_each_shadow_entry_lockless(_vcpu, _addr, _walker, spte)	\
+	for (shadow_walk_init(&(_walker), _vcpu, _addr);		\
+	     shadow_walk_okay(&(_walker)) &&				\
+		({ spte = mmu_spte_get_lockless(_walker.sptep); 1; });	\
+	     __shadow_walk_next(&(_walker), spte))
 
-static struct kmem_cache *pte_chain_cache;
-static struct kmem_cache *rmap_desc_cache;
+static struct kmem_cache *pte_list_desc_cache;
 static struct kmem_cache *mmu_page_header_cache;
 static struct percpu_counter kvm_total_used_mmu_pages;
 
-static u64 __read_mostly shadow_trap_nonpresent_pte;
-static u64 __read_mostly shadow_notrap_nonpresent_pte;
 static u64 __read_mostly shadow_nx_mask;
 static u64 __read_mostly shadow_x_mask;	/* mutual exclusive with nx_mask */
 static u64 __read_mostly shadow_user_mask;
 static u64 __read_mostly shadow_accessed_mask;
 static u64 __read_mostly shadow_dirty_mask;
+static u64 __read_mostly shadow_mmio_mask;
 
-static inline u64 rsvd_bits(int s, int e)
+static void mmu_spte_set(u64 *sptep, u64 spte);
+
+void kvm_mmu_set_mmio_spte_mask(u64 mmio_mask)
 {
-	return ((1ULL << (e - s + 1)) - 1) << s;
+	shadow_mmio_mask = mmio_mask;
+}
+EXPORT_SYMBOL_GPL(kvm_mmu_set_mmio_spte_mask);
+
+static void mark_mmio_spte(u64 *sptep, u64 gfn, unsigned access)
+{
+	access &= ACC_WRITE_MASK | ACC_USER_MASK;
+
+	trace_mark_mmio_spte(sptep, gfn, access);
+	mmu_spte_set(sptep, shadow_mmio_mask | access | gfn << PAGE_SHIFT);
 }
 
-void kvm_mmu_set_nonpresent_ptes(u64 trap_pte, u64 notrap_pte)
+static bool is_mmio_spte(u64 spte)
 {
-	shadow_trap_nonpresent_pte = trap_pte;
-	shadow_notrap_nonpresent_pte = notrap_pte;
+	return (spte & shadow_mmio_mask) == shadow_mmio_mask;
+}
+
+static gfn_t get_mmio_spte_gfn(u64 spte)
+{
+	return (spte & ~shadow_mmio_mask) >> PAGE_SHIFT;
+}
+
+static unsigned get_mmio_spte_access(u64 spte)
+{
+	return (spte & ~shadow_mmio_mask) & ~PAGE_MASK;
+}
+
+static bool set_mmio_spte(u64 *sptep, gfn_t gfn, pfn_t pfn, unsigned access)
+{
+	if (unlikely(is_noslot_pfn(pfn))) {
+		mark_mmio_spte(sptep, gfn, access);
+		return true;
+	}
+
+	return false;
+}
+
+static inline u64 rsvd_bits(int s, int e)
+{
+	return ((1ULL << (e - s + 1)) - 1) << s;
 }
-EXPORT_SYMBOL_GPL(kvm_mmu_set_nonpresent_ptes);
 
 void kvm_mmu_set_mask_ptes(u64 user_mask, u64 accessed_mask,
 		u64 dirty_mask, u64 nx_mask, u64 x_mask)
@@ -220,11 +256,6 @@ void kvm_mmu_set_mask_ptes(u64 user_mask, u64 accessed_mask,
 }
 EXPORT_SYMBOL_GPL(kvm_mmu_set_mask_ptes);
 
-static bool is_write_protection(struct kvm_vcpu *vcpu)
-{
-	return kvm_read_cr0_bits(vcpu, X86_CR0_WP);
-}
-
 static int is_cpuid_PSE36(void)
 {
 	return 1;
@@ -237,8 +268,7 @@ static int is_nx(struct kvm_vcpu *vcpu)
 
 static int is_shadow_present_pte(u64 pte)
 {
-	return pte != shadow_trap_nonpresent_pte
-		&& pte != shadow_notrap_nonpresent_pte;
+	return pte & PT_PRESENT_MASK && !is_mmio_spte(pte);
 }
 
 static int is_large_pte(u64 pte)
@@ -246,11 +276,6 @@ static int is_large_pte(u64 pte)
 	return pte & PT_PAGE_SIZE_MASK;
 }
 
-static int is_writable_pte(unsigned long pte)
-{
-	return pte & PT_WRITABLE_MASK;
-}
-
 static int is_dirty_gpte(unsigned long pte)
 {
 	return pte & PT_DIRTY_MASK;
@@ -282,26 +307,154 @@ static gfn_t pse36_gfn_delta(u32 gpte)
 	return (gpte & PT32_DIR_PSE36_MASK) << shift;
 }
 
+#ifdef CONFIG_X86_64
 static void __set_spte(u64 *sptep, u64 spte)
 {
-	set_64bit(sptep, spte);
+	*sptep = spte;
 }
 
-static u64 __xchg_spte(u64 *sptep, u64 new_spte)
+static void __update_clear_spte_fast(u64 *sptep, u64 spte)
 {
-#ifdef CONFIG_X86_64
-	return xchg(sptep, new_spte);
+	*sptep = spte;
+}
+
+static u64 __update_clear_spte_slow(u64 *sptep, u64 spte)
+{
+	return xchg(sptep, spte);
+}
+
+static u64 __get_spte_lockless(u64 *sptep)
+{
+	return ACCESS_ONCE(*sptep);
+}
+
+static bool __check_direct_spte_mmio_pf(u64 spte)
+{
+	/* It is valid if the spte is zapped. */
+	return spte == 0ull;
+}
 #else
-	u64 old_spte;
+union split_spte {
+	struct {
+		u32 spte_low;
+		u32 spte_high;
+	};
+	u64 spte;
+};
 
-	do {
-		old_spte = *sptep;
-	} while (cmpxchg64(sptep, old_spte, new_spte) != old_spte);
+static void count_spte_clear(u64 *sptep, u64 spte)
+{
+	struct kvm_mmu_page *sp =  page_header(__pa(sptep));
 
-	return old_spte;
-#endif
+	if (is_shadow_present_pte(spte))
+		return;
+
+	/* Ensure the spte is completely set before we increase the count */
+	smp_wmb();
+	sp->clear_spte_count++;
+}
+
+static void __set_spte(u64 *sptep, u64 spte)
+{
+	union split_spte *ssptep, sspte;
+
+	ssptep = (union split_spte *)sptep;
+	sspte = (union split_spte)spte;
+
+	ssptep->spte_high = sspte.spte_high;
+
+	/*
+	 * If we map the spte from nonpresent to present, We should store
+	 * the high bits firstly, then set present bit, so cpu can not
+	 * fetch this spte while we are setting the spte.
+	 */
+	smp_wmb();
+
+	ssptep->spte_low = sspte.spte_low;
 }
 
+static void __update_clear_spte_fast(u64 *sptep, u64 spte)
+{
+	union split_spte *ssptep, sspte;
+
+	ssptep = (union split_spte *)sptep;
+	sspte = (union split_spte)spte;
+
+	ssptep->spte_low = sspte.spte_low;
+
+	/*
+	 * If we map the spte from present to nonpresent, we should clear
+	 * present bit firstly to avoid vcpu fetch the old high bits.
+	 */
+	smp_wmb();
+
+	ssptep->spte_high = sspte.spte_high;
+	count_spte_clear(sptep, spte);
+}
+
+static u64 __update_clear_spte_slow(u64 *sptep, u64 spte)
+{
+	union split_spte *ssptep, sspte, orig;
+
+	ssptep = (union split_spte *)sptep;
+	sspte = (union split_spte)spte;
+
+	/* xchg acts as a barrier before the setting of the high bits */
+	orig.spte_low = xchg(&ssptep->spte_low, sspte.spte_low);
+	orig.spte_high = ssptep->spte_high = sspte.spte_high;
+	count_spte_clear(sptep, spte);
+
+	return orig.spte;
+}
+
+/*
+ * The idea using the light way get the spte on x86_32 guest is from
+ * gup_get_pte(arch/x86/mm/gup.c).
+ * The difference is we can not catch the spte tlb flush if we leave
+ * guest mode, so we emulate it by increase clear_spte_count when spte
+ * is cleared.
+ */
+static u64 __get_spte_lockless(u64 *sptep)
+{
+	struct kvm_mmu_page *sp =  page_header(__pa(sptep));
+	union split_spte spte, *orig = (union split_spte *)sptep;
+	int count;
+
+retry:
+	count = sp->clear_spte_count;
+	smp_rmb();
+
+	spte.spte_low = orig->spte_low;
+	smp_rmb();
+
+	spte.spte_high = orig->spte_high;
+	smp_rmb();
+
+	if (unlikely(spte.spte_low != orig->spte_low ||
+	      count != sp->clear_spte_count))
+		goto retry;
+
+	return spte.spte;
+}
+
+static bool __check_direct_spte_mmio_pf(u64 spte)
+{
+	union split_spte sspte = (union split_spte)spte;
+	u32 high_mmio_mask = shadow_mmio_mask >> 32;
+
+	/* It is valid if the spte is zapped. */
+	if (spte == 0ull)
+		return true;
+
+	/* It is valid if the spte is being zapped. */
+	if (sspte.spte_low == 0ull &&
+	    (sspte.spte_high & high_mmio_mask) == high_mmio_mask)
+		return true;
+
+	return false;
+}
+#endif
+
 static bool spte_has_volatile_bits(u64 spte)
 {
 	if (!shadow_accessed_mask)
@@ -322,12 +475,30 @@ static bool spte_is_bit_cleared(u64 old_spte, u64 new_spte, u64 bit_mask)
 	return (old_spte & bit_mask) && !(new_spte & bit_mask);
 }
 
-static void update_spte(u64 *sptep, u64 new_spte)
+/* Rules for using mmu_spte_set:
+ * Set the sptep from nonpresent to present.
+ * Note: the sptep being assigned *must* be either not present
+ * or in a state where the hardware will not attempt to update
+ * the spte.
+ */
+static void mmu_spte_set(u64 *sptep, u64 new_spte)
+{
+	WARN_ON(is_shadow_present_pte(*sptep));
+	__set_spte(sptep, new_spte);
+}
+
+/* Rules for using mmu_spte_update:
+ * Update the state bits, it means the mapped pfn is not changged.
+ */
+static void mmu_spte_update(u64 *sptep, u64 new_spte)
 {
 	u64 mask, old_spte = *sptep;
 
 	WARN_ON(!is_rmap_spte(new_spte));
 
+	if (!is_shadow_present_pte(old_spte))
+		return mmu_spte_set(sptep, new_spte);
+
 	new_spte |= old_spte & shadow_dirty_mask;
 
 	mask = shadow_accessed_mask;
@@ -335,9 +506,9 @@ static void update_spte(u64 *sptep, u64 new_spte)
 		mask |= shadow_dirty_mask;
 
 	if (!spte_has_volatile_bits(old_spte) || (new_spte & mask) == mask)
-		__set_spte(sptep, new_spte);
+		__update_clear_spte_fast(sptep, new_spte);
 	else
-		old_spte = __xchg_spte(sptep, new_spte);
+		old_spte = __update_clear_spte_slow(sptep, new_spte);
 
 	if (!shadow_accessed_mask)
 		return;
@@ -348,6 +519,64 @@ static void update_spte(u64 *sptep, u64 new_spte)
 		kvm_set_pfn_dirty(spte_to_pfn(old_spte));
 }
 
+/*
+ * Rules for using mmu_spte_clear_track_bits:
+ * It sets the sptep from present to nonpresent, and track the
+ * state bits, it is used to clear the last level sptep.
+ */
+static int mmu_spte_clear_track_bits(u64 *sptep)
+{
+	pfn_t pfn;
+	u64 old_spte = *sptep;
+
+	if (!spte_has_volatile_bits(old_spte))
+		__update_clear_spte_fast(sptep, 0ull);
+	else
+		old_spte = __update_clear_spte_slow(sptep, 0ull);
+
+	if (!is_rmap_spte(old_spte))
+		return 0;
+
+	pfn = spte_to_pfn(old_spte);
+	if (!shadow_accessed_mask || old_spte & shadow_accessed_mask)
+		kvm_set_pfn_accessed(pfn);
+	if (!shadow_dirty_mask || (old_spte & shadow_dirty_mask))
+		kvm_set_pfn_dirty(pfn);
+	return 1;
+}
+
+/*
+ * Rules for using mmu_spte_clear_no_track:
+ * Directly clear spte without caring the state bits of sptep,
+ * it is used to set the upper level spte.
+ */
+static void mmu_spte_clear_no_track(u64 *sptep)
+{
+	__update_clear_spte_fast(sptep, 0ull);
+}
+
+static u64 mmu_spte_get_lockless(u64 *sptep)
+{
+	return __get_spte_lockless(sptep);
+}
+
+static void walk_shadow_page_lockless_begin(struct kvm_vcpu *vcpu)
+{
+	rcu_read_lock();
+	atomic_inc(&vcpu->kvm->arch.reader_counter);
+
+	/* Increase the counter before walking shadow page table */
+	smp_mb__after_atomic_inc();
+}
+
+static void walk_shadow_page_lockless_end(struct kvm_vcpu *vcpu)
+{
+	/* Decrease the counter after walking shadow page table finished */
+	smp_mb__before_atomic_dec();
+	atomic_dec(&vcpu->kvm->arch.reader_counter);
+	rcu_read_unlock();
+}
+
 static int mmu_topup_memory_cache(struct kvm_mmu_memory_cache *cache,
 				  struct kmem_cache *base_cache, int min)
 {
@@ -397,12 +626,8 @@ static int mmu_topup_memory_caches(struct kvm_vcpu *vcpu)
 {
 	int r;
 
-	r = mmu_topup_memory_cache(&vcpu->arch.mmu_pte_chain_cache,
-				   pte_chain_cache, 4);
-	if (r)
-		goto out;
-	r = mmu_topup_memory_cache(&vcpu->arch.mmu_rmap_desc_cache,
-				   rmap_desc_cache, 4 + PTE_PREFETCH_NUM);
+	r = mmu_topup_memory_cache(&vcpu->arch.mmu_pte_list_desc_cache,
+				   pte_list_desc_cache, 8 + PTE_PREFETCH_NUM);
 	if (r)
 		goto out;
 	r = mmu_topup_memory_cache_page(&vcpu->arch.mmu_page_cache, 8);
@@ -416,8 +641,8 @@ out:
 
 static void mmu_free_memory_caches(struct kvm_vcpu *vcpu)
 {
-	mmu_free_memory_cache(&vcpu->arch.mmu_pte_chain_cache, pte_chain_cache);
-	mmu_free_memory_cache(&vcpu->arch.mmu_rmap_desc_cache, rmap_desc_cache);
+	mmu_free_memory_cache(&vcpu->arch.mmu_pte_list_desc_cache,
+				pte_list_desc_cache);
 	mmu_free_memory_cache_page(&vcpu->arch.mmu_page_cache);
 	mmu_free_memory_cache(&vcpu->arch.mmu_page_header_cache,
 				mmu_page_header_cache);
@@ -433,26 +658,15 @@ static void *mmu_memory_cache_alloc(struct kvm_mmu_memory_cache *mc,
 	return p;
 }
 
-static struct kvm_pte_chain *mmu_alloc_pte_chain(struct kvm_vcpu *vcpu)
-{
-	return mmu_memory_cache_alloc(&vcpu->arch.mmu_pte_chain_cache,
-				      sizeof(struct kvm_pte_chain));
-}
-
-static void mmu_free_pte_chain(struct kvm_pte_chain *pc)
+static struct pte_list_desc *mmu_alloc_pte_list_desc(struct kvm_vcpu *vcpu)
 {
-	kmem_cache_free(pte_chain_cache, pc);
+	return mmu_memory_cache_alloc(&vcpu->arch.mmu_pte_list_desc_cache,
+				      sizeof(struct pte_list_desc));
 }
 
-static struct kvm_rmap_desc *mmu_alloc_rmap_desc(struct kvm_vcpu *vcpu)
+static void mmu_free_pte_list_desc(struct pte_list_desc *pte_list_desc)
 {
-	return mmu_memory_cache_alloc(&vcpu->arch.mmu_rmap_desc_cache,
-				      sizeof(struct kvm_rmap_desc));
-}
-
-static void mmu_free_rmap_desc(struct kvm_rmap_desc *rd)
-{
-	kmem_cache_free(rmap_desc_cache, rd);
+	kmem_cache_free(pte_list_desc_cache, pte_list_desc);
 }
 
 static gfn_t kvm_mmu_page_get_gfn(struct kvm_mmu_page *sp, int index)
@@ -498,6 +712,7 @@ static void account_shadowed(struct kvm *kvm, gfn_t gfn)
 		linfo = lpage_info_slot(gfn, slot, i);
 		linfo->write_count += 1;
 	}
+	kvm->arch.indirect_shadow_pages++;
 }
 
 static void unaccount_shadowed(struct kvm *kvm, gfn_t gfn)
@@ -513,6 +728,7 @@ static void unaccount_shadowed(struct kvm *kvm, gfn_t gfn)
 		linfo->write_count -= 1;
 		WARN_ON(linfo->write_count < 0);
 	}
+	kvm->arch.indirect_shadow_pages--;
 }
 
 static int has_wrprotected_page(struct kvm *kvm,
@@ -588,67 +804,42 @@ static int mapping_level(struct kvm_vcpu *vcpu, gfn_t large_gfn)
 }
 
 /*
- * Take gfn and return the reverse mapping to it.
- */
-
-static unsigned long *gfn_to_rmap(struct kvm *kvm, gfn_t gfn, int level)
-{
-	struct kvm_memory_slot *slot;
-	struct kvm_lpage_info *linfo;
-
-	slot = gfn_to_memslot(kvm, gfn);
-	if (likely(level == PT_PAGE_TABLE_LEVEL))
-		return &slot->rmap[gfn - slot->base_gfn];
-
-	linfo = lpage_info_slot(gfn, slot, level);
-
-	return &linfo->rmap_pde;
-}
-
-/*
- * Reverse mapping data structures:
+ * Pte mapping structures:
  *
- * If rmapp bit zero is zero, then rmapp point to the shadw page table entry
- * that points to page_address(page).
+ * If pte_list bit zero is zero, then pte_list point to the spte.
  *
- * If rmapp bit zero is one, (then rmap & ~1) points to a struct kvm_rmap_desc
- * containing more mappings.
+ * If pte_list bit zero is one, (then pte_list & ~1) points to a struct
+ * pte_list_desc containing more mappings.
  *
- * Returns the number of rmap entries before the spte was added or zero if
+ * Returns the number of pte entries before the spte was added or zero if
  * the spte was not added.
  *
  */
-static int rmap_add(struct kvm_vcpu *vcpu, u64 *spte, gfn_t gfn)
+static int pte_list_add(struct kvm_vcpu *vcpu, u64 *spte,
+			unsigned long *pte_list)
 {
-	struct kvm_mmu_page *sp;
-	struct kvm_rmap_desc *desc;
-	unsigned long *rmapp;
+	struct pte_list_desc *desc;
 	int i, count = 0;
 
-	if (!is_rmap_spte(*spte))
-		return count;
-	sp = page_header(__pa(spte));
-	kvm_mmu_page_set_gfn(sp, spte - sp->spt, gfn);
-	rmapp = gfn_to_rmap(vcpu->kvm, gfn, sp->role.level);
-	if (!*rmapp) {
-		rmap_printk("rmap_add: %p %llx 0->1\n", spte, *spte);
-		*rmapp = (unsigned long)spte;
-	} else if (!(*rmapp & 1)) {
-		rmap_printk("rmap_add: %p %llx 1->many\n", spte, *spte);
-		desc = mmu_alloc_rmap_desc(vcpu);
-		desc->sptes[0] = (u64 *)*rmapp;
+	if (!*pte_list) {
+		rmap_printk("pte_list_add: %p %llx 0->1\n", spte, *spte);
+		*pte_list = (unsigned long)spte;
+	} else if (!(*pte_list & 1)) {
+		rmap_printk("pte_list_add: %p %llx 1->many\n", spte, *spte);
+		desc = mmu_alloc_pte_list_desc(vcpu);
+		desc->sptes[0] = (u64 *)*pte_list;
 		desc->sptes[1] = spte;
-		*rmapp = (unsigned long)desc | 1;
+		*pte_list = (unsigned long)desc | 1;
 		++count;
 	} else {
-		rmap_printk("rmap_add: %p %llx many->many\n", spte, *spte);
-		desc = (struct kvm_rmap_desc *)(*rmapp & ~1ul);
-		while (desc->sptes[RMAP_EXT-1] && desc->more) {
+		rmap_printk("pte_list_add: %p %llx many->many\n", spte, *spte);
+		desc = (struct pte_list_desc *)(*pte_list & ~1ul);
+		while (desc->sptes[PTE_LIST_EXT-1] && desc->more) {
 			desc = desc->more;
-			count += RMAP_EXT;
+			count += PTE_LIST_EXT;
 		}
-		if (desc->sptes[RMAP_EXT-1]) {
-			desc->more = mmu_alloc_rmap_desc(vcpu);
+		if (desc->sptes[PTE_LIST_EXT-1]) {
+			desc->more = mmu_alloc_pte_list_desc(vcpu);
 			desc = desc->more;
 		}
 		for (i = 0; desc->sptes[i]; ++i)
@@ -658,59 +849,78 @@ static int rmap_add(struct kvm_vcpu *vcpu, u64 *spte, gfn_t gfn)
 	return count;
 }
 
-static void rmap_desc_remove_entry(unsigned long *rmapp,
-				   struct kvm_rmap_desc *desc,
-				   int i,
-				   struct kvm_rmap_desc *prev_desc)
+static u64 *pte_list_next(unsigned long *pte_list, u64 *spte)
+{
+	struct pte_list_desc *desc;
+	u64 *prev_spte;
+	int i;
+
+	if (!*pte_list)
+		return NULL;
+	else if (!(*pte_list & 1)) {
+		if (!spte)
+			return (u64 *)*pte_list;
+		return NULL;
+	}
+	desc = (struct pte_list_desc *)(*pte_list & ~1ul);
+	prev_spte = NULL;
+	while (desc) {
+		for (i = 0; i < PTE_LIST_EXT && desc->sptes[i]; ++i) {
+			if (prev_spte == spte)
+				return desc->sptes[i];
+			prev_spte = desc->sptes[i];
+		}
+		desc = desc->more;
+	}
+	return NULL;
+}
+
+static void
+pte_list_desc_remove_entry(unsigned long *pte_list, struct pte_list_desc *desc,
+			   int i, struct pte_list_desc *prev_desc)
 {
 	int j;
 
-	for (j = RMAP_EXT - 1; !desc->sptes[j] && j > i; --j)
+	for (j = PTE_LIST_EXT - 1; !desc->sptes[j] && j > i; --j)
 		;
 	desc->sptes[i] = desc->sptes[j];
 	desc->sptes[j] = NULL;
 	if (j != 0)
 		return;
 	if (!prev_desc && !desc->more)
-		*rmapp = (unsigned long)desc->sptes[0];
+		*pte_list = (unsigned long)desc->sptes[0];
 	else
 		if (prev_desc)
 			prev_desc->more = desc->more;
 		else
-			*rmapp = (unsigned long)desc->more | 1;
-	mmu_free_rmap_desc(desc);
+			*pte_list = (unsigned long)desc->more | 1;
+	mmu_free_pte_list_desc(desc);
 }
 
-static void rmap_remove(struct kvm *kvm, u64 *spte)
+static void pte_list_remove(u64 *spte, unsigned long *pte_list)
 {
-	struct kvm_rmap_desc *desc;
-	struct kvm_rmap_desc *prev_desc;
-	struct kvm_mmu_page *sp;
-	gfn_t gfn;
-	unsigned long *rmapp;
+	struct pte_list_desc *desc;
+	struct pte_list_desc *prev_desc;
 	int i;
 
-	sp = page_header(__pa(spte));
-	gfn = kvm_mmu_page_get_gfn(sp, spte - sp->spt);
-	rmapp = gfn_to_rmap(kvm, gfn, sp->role.level);
-	if (!*rmapp) {
-		printk(KERN_ERR "rmap_remove: %p 0->BUG\n", spte);
+	if (!*pte_list) {
+		printk(KERN_ERR "pte_list_remove: %p 0->BUG\n", spte);
 		BUG();
-	} else if (!(*rmapp & 1)) {
-		rmap_printk("rmap_remove:  %p 1->0\n", spte);
-		if ((u64 *)*rmapp != spte) {
-			printk(KERN_ERR "rmap_remove:  %p 1->BUG\n", spte);
+	} else if (!(*pte_list & 1)) {
+		rmap_printk("pte_list_remove:  %p 1->0\n", spte);
+		if ((u64 *)*pte_list != spte) {
+			printk(KERN_ERR "pte_list_remove:  %p 1->BUG\n", spte);
 			BUG();
 		}
-		*rmapp = 0;
+		*pte_list = 0;
 	} else {
-		rmap_printk("rmap_remove:  %p many->many\n", spte);
-		desc = (struct kvm_rmap_desc *)(*rmapp & ~1ul);
+		rmap_printk("pte_list_remove:  %p many->many\n", spte);
+		desc = (struct pte_list_desc *)(*pte_list & ~1ul);
 		prev_desc = NULL;
 		while (desc) {
-			for (i = 0; i < RMAP_EXT && desc->sptes[i]; ++i)
+			for (i = 0; i < PTE_LIST_EXT && desc->sptes[i]; ++i)
 				if (desc->sptes[i] == spte) {
-					rmap_desc_remove_entry(rmapp,
+					pte_list_desc_remove_entry(pte_list,
 							       desc, i,
 							       prev_desc);
 					return;
@@ -718,62 +928,80 @@ static void rmap_remove(struct kvm *kvm, u64 *spte)
 			prev_desc = desc;
 			desc = desc->more;
 		}
-		pr_err("rmap_remove: %p many->many\n", spte);
+		pr_err("pte_list_remove: %p many->many\n", spte);
 		BUG();
 	}
 }
 
-static int set_spte_track_bits(u64 *sptep, u64 new_spte)
+typedef void (*pte_list_walk_fn) (u64 *spte);
+static void pte_list_walk(unsigned long *pte_list, pte_list_walk_fn fn)
 {
-	pfn_t pfn;
-	u64 old_spte = *sptep;
+	struct pte_list_desc *desc;
+	int i;
 
-	if (!spte_has_volatile_bits(old_spte))
-		__set_spte(sptep, new_spte);
-	else
-		old_spte = __xchg_spte(sptep, new_spte);
+	if (!*pte_list)
+		return;
 
-	if (!is_rmap_spte(old_spte))
-		return 0;
+	if (!(*pte_list & 1))
+		return fn((u64 *)*pte_list);
 
-	pfn = spte_to_pfn(old_spte);
-	if (!shadow_accessed_mask || old_spte & shadow_accessed_mask)
-		kvm_set_pfn_accessed(pfn);
-	if (!shadow_dirty_mask || (old_spte & shadow_dirty_mask))
-		kvm_set_pfn_dirty(pfn);
-	return 1;
+	desc = (struct pte_list_desc *)(*pte_list & ~1ul);
+	while (desc) {
+		for (i = 0; i < PTE_LIST_EXT && desc->sptes[i]; ++i)
+			fn(desc->sptes[i]);
+		desc = desc->more;
+	}
 }
 
-static void drop_spte(struct kvm *kvm, u64 *sptep, u64 new_spte)
+/*
+ * Take gfn and return the reverse mapping to it.
+ */
+static unsigned long *gfn_to_rmap(struct kvm *kvm, gfn_t gfn, int level)
 {
-	if (set_spte_track_bits(sptep, new_spte))
-		rmap_remove(kvm, sptep);
+	struct kvm_memory_slot *slot;
+	struct kvm_lpage_info *linfo;
+
+	slot = gfn_to_memslot(kvm, gfn);
+	if (likely(level == PT_PAGE_TABLE_LEVEL))
+		return &slot->rmap[gfn - slot->base_gfn];
+
+	linfo = lpage_info_slot(gfn, slot, level);
+
+	return &linfo->rmap_pde;
+}
+
+static int rmap_add(struct kvm_vcpu *vcpu, u64 *spte, gfn_t gfn)
+{
+	struct kvm_mmu_page *sp;
+	unsigned long *rmapp;
+
+	sp = page_header(__pa(spte));
+	kvm_mmu_page_set_gfn(sp, spte - sp->spt, gfn);
+	rmapp = gfn_to_rmap(vcpu->kvm, gfn, sp->role.level);
+	return pte_list_add(vcpu, spte, rmapp);
 }
 
 static u64 *rmap_next(struct kvm *kvm, unsigned long *rmapp, u64 *spte)
 {
-	struct kvm_rmap_desc *desc;
-	u64 *prev_spte;
-	int i;
+	return pte_list_next(rmapp, spte);
+}
 
-	if (!*rmapp)
-		return NULL;
-	else if (!(*rmapp & 1)) {
-		if (!spte)
-			return (u64 *)*rmapp;
-		return NULL;
-	}
-	desc = (struct kvm_rmap_desc *)(*rmapp & ~1ul);
-	prev_spte = NULL;
-	while (desc) {
-		for (i = 0; i < RMAP_EXT && desc->sptes[i]; ++i) {
-			if (prev_spte == spte)
-				return desc->sptes[i];
-			prev_spte = desc->sptes[i];
-		}
-		desc = desc->more;
-	}
-	return NULL;
+static void rmap_remove(struct kvm *kvm, u64 *spte)
+{
+	struct kvm_mmu_page *sp;
+	gfn_t gfn;
+	unsigned long *rmapp;
+
+	sp = page_header(__pa(spte));
+	gfn = kvm_mmu_page_get_gfn(sp, spte - sp->spt);
+	rmapp = gfn_to_rmap(kvm, gfn, sp->role.level);
+	pte_list_remove(spte, rmapp);
+}
+
+static void drop_spte(struct kvm *kvm, u64 *sptep)
+{
+	if (mmu_spte_clear_track_bits(sptep))
+		rmap_remove(kvm, sptep);
 }
 
 static int rmap_write_protect(struct kvm *kvm, u64 gfn)
@@ -790,7 +1018,7 @@ static int rmap_write_protect(struct kvm *kvm, u64 gfn)
 		BUG_ON(!(*spte & PT_PRESENT_MASK));
 		rmap_printk("rmap_write_protect: spte %p %llx\n", spte, *spte);
 		if (is_writable_pte(*spte)) {
-			update_spte(spte, *spte & ~PT_WRITABLE_MASK);
+			mmu_spte_update(spte, *spte & ~PT_WRITABLE_MASK);
 			write_protected = 1;
 		}
 		spte = rmap_next(kvm, rmapp, spte);
@@ -807,8 +1035,7 @@ static int rmap_write_protect(struct kvm *kvm, u64 gfn)
 			BUG_ON((*spte & (PT_PAGE_SIZE_MASK|PT_PRESENT_MASK)) != (PT_PAGE_SIZE_MASK|PT_PRESENT_MASK));
 			pgprintk("rmap_write_protect(large): spte %p %llx %lld\n", spte, *spte, gfn);
 			if (is_writable_pte(*spte)) {
-				drop_spte(kvm, spte,
-					  shadow_trap_nonpresent_pte);
+				drop_spte(kvm, spte);
 				--kvm->stat.lpages;
 				spte = NULL;
 				write_protected = 1;
@@ -829,7 +1056,7 @@ static int kvm_unmap_rmapp(struct kvm *kvm, unsigned long *rmapp,
 	while ((spte = rmap_next(kvm, rmapp, NULL))) {
 		BUG_ON(!(*spte & PT_PRESENT_MASK));
 		rmap_printk("kvm_rmap_unmap_hva: spte %p %llx\n", spte, *spte);
-		drop_spte(kvm, spte, shadow_trap_nonpresent_pte);
+		drop_spte(kvm, spte);
 		need_tlb_flush = 1;
 	}
 	return need_tlb_flush;
@@ -851,7 +1078,7 @@ static int kvm_set_pte_rmapp(struct kvm *kvm, unsigned long *rmapp,
 		rmap_printk("kvm_set_pte_rmapp: spte %p %llx\n", spte, *spte);
 		need_flush = 1;
 		if (pte_write(*ptep)) {
-			drop_spte(kvm, spte, shadow_trap_nonpresent_pte);
+			drop_spte(kvm, spte);
 			spte = rmap_next(kvm, rmapp, NULL);
 		} else {
 			new_spte = *spte &~ (PT64_BASE_ADDR_MASK);
@@ -860,7 +1087,8 @@ static int kvm_set_pte_rmapp(struct kvm *kvm, unsigned long *rmapp,
 			new_spte &= ~PT_WRITABLE_MASK;
 			new_spte &= ~SPTE_HOST_WRITEABLE;
 			new_spte &= ~shadow_accessed_mask;
-			set_spte_track_bits(spte, new_spte);
+			mmu_spte_clear_track_bits(spte);
+			mmu_spte_set(spte, new_spte);
 			spte = rmap_next(kvm, rmapp, spte);
 		}
 	}
@@ -1032,151 +1260,89 @@ static inline void kvm_mod_used_mmu_pages(struct kvm *kvm, int nr)
 	percpu_counter_add(&kvm_total_used_mmu_pages, nr);
 }
 
-static void kvm_mmu_free_page(struct kvm *kvm, struct kvm_mmu_page *sp)
+/*
+ * Remove the sp from shadow page cache, after call it,
+ * we can not find this sp from the cache, and the shadow
+ * page table is still valid.
+ * It should be under the protection of mmu lock.
+ */
+static void kvm_mmu_isolate_page(struct kvm_mmu_page *sp)
 {
 	ASSERT(is_empty_shadow_page(sp->spt));
 	hlist_del(&sp->hash_link);
-	list_del(&sp->link);
-	free_page((unsigned long)sp->spt);
 	if (!sp->role.direct)
 		free_page((unsigned long)sp->gfns);
-	kmem_cache_free(mmu_page_header_cache, sp);
-	kvm_mod_used_mmu_pages(kvm, -1);
 }
 
-static unsigned kvm_page_table_hashfn(gfn_t gfn)
+/*
+ * Free the shadow page table and the sp, we can do it
+ * out of the protection of mmu lock.
+ */
+static void kvm_mmu_free_page(struct kvm_mmu_page *sp)
 {
-	return gfn & ((1 << KVM_MMU_HASH_SHIFT) - 1);
+	list_del(&sp->link);
+	free_page((unsigned long)sp->spt);
+	kmem_cache_free(mmu_page_header_cache, sp);
 }
 
-static struct kvm_mmu_page *kvm_mmu_alloc_page(struct kvm_vcpu *vcpu,
-					       u64 *parent_pte, int direct)
+static unsigned kvm_page_table_hashfn(gfn_t gfn)
 {
-	struct kvm_mmu_page *sp;
-
-	sp = mmu_memory_cache_alloc(&vcpu->arch.mmu_page_header_cache, sizeof *sp);
-	sp->spt = mmu_memory_cache_alloc(&vcpu->arch.mmu_page_cache, PAGE_SIZE);
-	if (!direct)
-		sp->gfns = mmu_memory_cache_alloc(&vcpu->arch.mmu_page_cache,
-						  PAGE_SIZE);
-	set_page_private(virt_to_page(sp->spt), (unsigned long)sp);
-	list_add(&sp->link, &vcpu->kvm->arch.active_mmu_pages);
-	bitmap_zero(sp->slot_bitmap, KVM_MEMORY_SLOTS + KVM_PRIVATE_MEM_SLOTS);
-	sp->multimapped = 0;
-	sp->parent_pte = parent_pte;
-	kvm_mod_used_mmu_pages(vcpu->kvm, +1);
-	return sp;
+	return gfn & ((1 << KVM_MMU_HASH_SHIFT) - 1);
 }
 
 static void mmu_page_add_parent_pte(struct kvm_vcpu *vcpu,
 				    struct kvm_mmu_page *sp, u64 *parent_pte)
 {
-	struct kvm_pte_chain *pte_chain;
-	struct hlist_node *node;
-	int i;
-
 	if (!parent_pte)
 		return;
-	if (!sp->multimapped) {
-		u64 *old = sp->parent_pte;
 
-		if (!old) {
-			sp->parent_pte = parent_pte;
-			return;
-		}
-		sp->multimapped = 1;
-		pte_chain = mmu_alloc_pte_chain(vcpu);
-		INIT_HLIST_HEAD(&sp->parent_ptes);
-		hlist_add_head(&pte_chain->link, &sp->parent_ptes);
-		pte_chain->parent_ptes[0] = old;
-	}
-	hlist_for_each_entry(pte_chain, node, &sp->parent_ptes, link) {
-		if (pte_chain->parent_ptes[NR_PTE_CHAIN_ENTRIES-1])
-			continue;
-		for (i = 0; i < NR_PTE_CHAIN_ENTRIES; ++i)
-			if (!pte_chain->parent_ptes[i]) {
-				pte_chain->parent_ptes[i] = parent_pte;
-				return;
-			}
-	}
-	pte_chain = mmu_alloc_pte_chain(vcpu);
-	BUG_ON(!pte_chain);
-	hlist_add_head(&pte_chain->link, &sp->parent_ptes);
-	pte_chain->parent_ptes[0] = parent_pte;
+	pte_list_add(vcpu, parent_pte, &sp->parent_ptes);
 }
 
 static void mmu_page_remove_parent_pte(struct kvm_mmu_page *sp,
 				       u64 *parent_pte)
 {
-	struct kvm_pte_chain *pte_chain;
-	struct hlist_node *node;
-	int i;
-
-	if (!sp->multimapped) {
-		BUG_ON(sp->parent_pte != parent_pte);
-		sp->parent_pte = NULL;
-		return;
-	}
-	hlist_for_each_entry(pte_chain, node, &sp->parent_ptes, link)
-		for (i = 0; i < NR_PTE_CHAIN_ENTRIES; ++i) {
-			if (!pte_chain->parent_ptes[i])
-				break;
-			if (pte_chain->parent_ptes[i] != parent_pte)
-				continue;
-			while (i + 1 < NR_PTE_CHAIN_ENTRIES
-				&& pte_chain->parent_ptes[i + 1]) {
-				pte_chain->parent_ptes[i]
-					= pte_chain->parent_ptes[i + 1];
-				++i;
-			}
-			pte_chain->parent_ptes[i] = NULL;
-			if (i == 0) {
-				hlist_del(&pte_chain->link);
-				mmu_free_pte_chain(pte_chain);
-				if (hlist_empty(&sp->parent_ptes)) {
-					sp->multimapped = 0;
-					sp->parent_pte = NULL;
-				}
-			}
-			return;
-		}
-	BUG();
+	pte_list_remove(parent_pte, &sp->parent_ptes);
 }
 
-static void mmu_parent_walk(struct kvm_mmu_page *sp, mmu_parent_walk_fn fn)
+static void drop_parent_pte(struct kvm_mmu_page *sp,
+			    u64 *parent_pte)
 {
-	struct kvm_pte_chain *pte_chain;
-	struct hlist_node *node;
-	struct kvm_mmu_page *parent_sp;
-	int i;
-
-	if (!sp->multimapped && sp->parent_pte) {
-		parent_sp = page_header(__pa(sp->parent_pte));
-		fn(parent_sp, sp->parent_pte);
-		return;
-	}
-
-	hlist_for_each_entry(pte_chain, node, &sp->parent_ptes, link)
-		for (i = 0; i < NR_PTE_CHAIN_ENTRIES; ++i) {
-			u64 *spte = pte_chain->parent_ptes[i];
+	mmu_page_remove_parent_pte(sp, parent_pte);
+	mmu_spte_clear_no_track(parent_pte);
+}
 
-			if (!spte)
-				break;
-			parent_sp = page_header(__pa(spte));
-			fn(parent_sp, spte);
-		}
+static struct kvm_mmu_page *kvm_mmu_alloc_page(struct kvm_vcpu *vcpu,
+					       u64 *parent_pte, int direct)
+{
+	struct kvm_mmu_page *sp;
+	sp = mmu_memory_cache_alloc(&vcpu->arch.mmu_page_header_cache,
+					sizeof *sp);
+	sp->spt = mmu_memory_cache_alloc(&vcpu->arch.mmu_page_cache, PAGE_SIZE);
+	if (!direct)
+		sp->gfns = mmu_memory_cache_alloc(&vcpu->arch.mmu_page_cache,
+						  PAGE_SIZE);
+	set_page_private(virt_to_page(sp->spt), (unsigned long)sp);
+	list_add(&sp->link, &vcpu->kvm->arch.active_mmu_pages);
+	bitmap_zero(sp->slot_bitmap, KVM_MEMORY_SLOTS + KVM_PRIVATE_MEM_SLOTS);
+	sp->parent_ptes = 0;
+	mmu_page_add_parent_pte(vcpu, sp, parent_pte);
+	kvm_mod_used_mmu_pages(vcpu->kvm, +1);
+	return sp;
 }
 
-static void mark_unsync(struct kvm_mmu_page *sp, u64 *spte);
+static void mark_unsync(u64 *spte);
 static void kvm_mmu_mark_parents_unsync(struct kvm_mmu_page *sp)
 {
-	mmu_parent_walk(sp, mark_unsync);
+	pte_list_walk(&sp->parent_ptes, mark_unsync);
 }
 
-static void mark_unsync(struct kvm_mmu_page *sp, u64 *spte)
+static void mark_unsync(u64 *spte)
 {
+	struct kvm_mmu_page *sp;
 	unsigned int index;
 
+	sp = page_header(__pa(spte));
 	index = spte - sp->spt;
 	if (__test_and_set_bit(index, sp->unsync_child_bitmap))
 		return;
@@ -1185,15 +1351,6 @@ static void mark_unsync(struct kvm_mmu_page *sp, u64 *spte)
 	kvm_mmu_mark_parents_unsync(sp);
 }
 
-static void nonpaging_prefetch_page(struct kvm_vcpu *vcpu,
-				    struct kvm_mmu_page *sp)
-{
-	int i;
-
-	for (i = 0; i < PT64_ENT_PER_PAGE; ++i)
-		sp->spt[i] = shadow_trap_nonpresent_pte;
-}
-
 static int nonpaging_sync_page(struct kvm_vcpu *vcpu,
 			       struct kvm_mmu_page *sp)
 {
@@ -1475,6 +1632,14 @@ static void mmu_sync_children(struct kvm_vcpu *vcpu,
 	}
 }
 
+static void init_shadow_page_table(struct kvm_mmu_page *sp)
+{
+	int i;
+
+	for (i = 0; i < PT64_ENT_PER_PAGE; ++i)
+		sp->spt[i] = 0ull;
+}
+
 static struct kvm_mmu_page *kvm_mmu_get_page(struct kvm_vcpu *vcpu,
 					     gfn_t gfn,
 					     gva_t gaddr,
@@ -1537,10 +1702,7 @@ static struct kvm_mmu_page *kvm_mmu_get_page(struct kvm_vcpu *vcpu,
 
 		account_shadowed(vcpu->kvm, gfn);
 	}
-	if (shadow_trap_nonpresent_pte != shadow_notrap_nonpresent_pte)
-		vcpu->arch.mmu.prefetch_page(vcpu, sp);
-	else
-		nonpaging_prefetch_page(vcpu, sp);
+	init_shadow_page_table(sp);
 	trace_kvm_mmu_get_page(sp, true);
 	return sp;
 }
@@ -1572,21 +1734,28 @@ static bool shadow_walk_okay(struct kvm_shadow_walk_iterator *iterator)
 	if (iterator->level < PT_PAGE_TABLE_LEVEL)
 		return false;
 
-	if (iterator->level == PT_PAGE_TABLE_LEVEL)
-		if (is_large_pte(*iterator->sptep))
-			return false;
-
 	iterator->index = SHADOW_PT_INDEX(iterator->addr, iterator->level);
 	iterator->sptep	= ((u64 *)__va(iterator->shadow_addr)) + iterator->index;
 	return true;
 }
 
-static void shadow_walk_next(struct kvm_shadow_walk_iterator *iterator)
+static void __shadow_walk_next(struct kvm_shadow_walk_iterator *iterator,
+			       u64 spte)
 {
-	iterator->shadow_addr = *iterator->sptep & PT64_BASE_ADDR_MASK;
+	if (is_last_spte(spte, iterator->level)) {
+		iterator->level = 0;
+		return;
+	}
+
+	iterator->shadow_addr = spte & PT64_BASE_ADDR_MASK;
 	--iterator->level;
 }
 
+static void shadow_walk_next(struct kvm_shadow_walk_iterator *iterator)
+{
+	return __shadow_walk_next(iterator, *iterator->sptep);
+}
+
 static void link_shadow_page(u64 *sptep, struct kvm_mmu_page *sp)
 {
 	u64 spte;
@@ -1594,13 +1763,13 @@ static void link_shadow_page(u64 *sptep, struct kvm_mmu_page *sp)
 	spte = __pa(sp->spt)
 		| PT_PRESENT_MASK | PT_ACCESSED_MASK
 		| PT_WRITABLE_MASK | PT_USER_MASK;
-	__set_spte(sptep, spte);
+	mmu_spte_set(sptep, spte);
 }
 
 static void drop_large_spte(struct kvm_vcpu *vcpu, u64 *sptep)
 {
 	if (is_large_pte(*sptep)) {
-		drop_spte(vcpu->kvm, sptep, shadow_trap_nonpresent_pte);
+		drop_spte(vcpu->kvm, sptep);
 		kvm_flush_remote_tlbs(vcpu->kvm);
 	}
 }
@@ -1622,38 +1791,39 @@ static void validate_direct_spte(struct kvm_vcpu *vcpu, u64 *sptep,
 		if (child->role.access == direct_access)
 			return;
 
-		mmu_page_remove_parent_pte(child, sptep);
-		__set_spte(sptep, shadow_trap_nonpresent_pte);
+		drop_parent_pte(child, sptep);
 		kvm_flush_remote_tlbs(vcpu->kvm);
 	}
 }
 
+static void mmu_page_zap_pte(struct kvm *kvm, struct kvm_mmu_page *sp,
+			     u64 *spte)
+{
+	u64 pte;
+	struct kvm_mmu_page *child;
+
+	pte = *spte;
+	if (is_shadow_present_pte(pte)) {
+		if (is_last_spte(pte, sp->role.level))
+			drop_spte(kvm, spte);
+		else {
+			child = page_header(pte & PT64_BASE_ADDR_MASK);
+			drop_parent_pte(child, spte);
+		}
+	} else if (is_mmio_spte(pte))
+		mmu_spte_clear_no_track(spte);
+
+	if (is_large_pte(pte))
+		--kvm->stat.lpages;
+}
+
 static void kvm_mmu_page_unlink_children(struct kvm *kvm,
 					 struct kvm_mmu_page *sp)
 {
 	unsigned i;
-	u64 *pt;
-	u64 ent;
-
-	pt = sp->spt;
-
-	for (i = 0; i < PT64_ENT_PER_PAGE; ++i) {
-		ent = pt[i];
-
-		if (is_shadow_present_pte(ent)) {
-			if (!is_last_spte(ent, sp->role.level)) {
-				ent &= PT64_BASE_ADDR_MASK;
-				mmu_page_remove_parent_pte(page_header(ent),
-							   &pt[i]);
-			} else {
-				if (is_large_pte(ent))
-					--kvm->stat.lpages;
-				drop_spte(kvm, &pt[i],
-					  shadow_trap_nonpresent_pte);
-			}
-		}
-		pt[i] = shadow_trap_nonpresent_pte;
-	}
+
+	for (i = 0; i < PT64_ENT_PER_PAGE; ++i)
+		mmu_page_zap_pte(kvm, sp, sp->spt + i);
 }
 
 static void kvm_mmu_put_page(struct kvm_mmu_page *sp, u64 *parent_pte)
@@ -1674,20 +1844,8 @@ static void kvm_mmu_unlink_parents(struct kvm *kvm, struct kvm_mmu_page *sp)
 {
 	u64 *parent_pte;
 
-	while (sp->multimapped || sp->parent_pte) {
-		if (!sp->multimapped)
-			parent_pte = sp->parent_pte;
-		else {
-			struct kvm_pte_chain *chain;
-
-			chain = container_of(sp->parent_ptes.first,
-					     struct kvm_pte_chain, link);
-			parent_pte = chain->parent_ptes[0];
-		}
-		BUG_ON(!parent_pte);
-		kvm_mmu_put_page(sp, parent_pte);
-		__set_spte(parent_pte, shadow_trap_nonpresent_pte);
-	}
+	while ((parent_pte = pte_list_next(&sp->parent_ptes, NULL)))
+		drop_parent_pte(sp, parent_pte);
 }
 
 static int mmu_zap_unsync_children(struct kvm *kvm,
@@ -1734,6 +1892,7 @@ static int kvm_mmu_prepare_zap_page(struct kvm *kvm, struct kvm_mmu_page *sp,
 		/* Count self */
 		ret++;
 		list_move(&sp->link, invalid_list);
+		kvm_mod_used_mmu_pages(kvm, -1);
 	} else {
 		list_move(&sp->link, &kvm->arch.active_mmu_pages);
 		kvm_reload_remote_mmus(kvm);
@@ -1744,6 +1903,30 @@ static int kvm_mmu_prepare_zap_page(struct kvm *kvm, struct kvm_mmu_page *sp,
 	return ret;
 }
 
+static void kvm_mmu_isolate_pages(struct list_head *invalid_list)
+{
+	struct kvm_mmu_page *sp;
+
+	list_for_each_entry(sp, invalid_list, link)
+		kvm_mmu_isolate_page(sp);
+}
+
+static void free_pages_rcu(struct rcu_head *head)
+{
+	struct kvm_mmu_page *next, *sp;
+
+	sp = container_of(head, struct kvm_mmu_page, rcu);
+	while (sp) {
+		if (!list_empty(&sp->link))
+			next = list_first_entry(&sp->link,
+				      struct kvm_mmu_page, link);
+		else
+			next = NULL;
+		kvm_mmu_free_page(sp);
+		sp = next;
+	}
+}
+
 static void kvm_mmu_commit_zap_page(struct kvm *kvm,
 				    struct list_head *invalid_list)
 {
@@ -1754,10 +1937,21 @@ static void kvm_mmu_commit_zap_page(struct kvm *kvm,
 
 	kvm_flush_remote_tlbs(kvm);
 
+	if (atomic_read(&kvm->arch.reader_counter)) {
+		kvm_mmu_isolate_pages(invalid_list);
+		sp = list_first_entry(invalid_list, struct kvm_mmu_page, link);
+		list_del_init(invalid_list);
+
+		trace_kvm_mmu_delay_free_pages(sp);
+		call_rcu(&sp->rcu, free_pages_rcu);
+		return;
+	}
+
 	do {
 		sp = list_first_entry(invalid_list, struct kvm_mmu_page, link);
 		WARN_ON(!sp->role.invalid || sp->root_count);
-		kvm_mmu_free_page(kvm, sp);
+		kvm_mmu_isolate_page(sp);
+		kvm_mmu_free_page(sp);
 	} while (!list_empty(invalid_list));
 
 }
@@ -1783,8 +1977,8 @@ void kvm_mmu_change_mmu_pages(struct kvm *kvm, unsigned int goal_nr_mmu_pages)
 			page = container_of(kvm->arch.active_mmu_pages.prev,
 					    struct kvm_mmu_page, link);
 			kvm_mmu_prepare_zap_page(kvm, page, &invalid_list);
-			kvm_mmu_commit_zap_page(kvm, &invalid_list);
 		}
+		kvm_mmu_commit_zap_page(kvm, &invalid_list);
 		goal_nr_mmu_pages = kvm->arch.n_used_mmu_pages;
 	}
 
@@ -1833,20 +2027,6 @@ static void page_header_update_slot(struct kvm *kvm, void *pte, gfn_t gfn)
 	__set_bit(slot, sp->slot_bitmap);
 }
 
-static void mmu_convert_notrap(struct kvm_mmu_page *sp)
-{
-	int i;
-	u64 *pt = sp->spt;
-
-	if (shadow_trap_nonpresent_pte == shadow_notrap_nonpresent_pte)
-		return;
-
-	for (i = 0; i < PT64_ENT_PER_PAGE; ++i) {
-		if (pt[i] == shadow_notrap_nonpresent_pte)
-			__set_spte(&pt[i], shadow_trap_nonpresent_pte);
-	}
-}
-
 /*
  * The function is based on mtrr_type_lookup() in
  * arch/x86/kernel/cpu/mtrr/generic.c
@@ -1959,7 +2139,6 @@ static void __kvm_unsync_page(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp)
 	sp->unsync = 1;
 
 	kvm_mmu_mark_parents_unsync(sp);
-	mmu_convert_notrap(sp);
 }
 
 static void kvm_unsync_pages(struct kvm_vcpu *vcpu,  gfn_t gfn)
@@ -2002,13 +2181,16 @@ static int mmu_need_write_protect(struct kvm_vcpu *vcpu, gfn_t gfn,
 
 static int set_spte(struct kvm_vcpu *vcpu, u64 *sptep,
 		    unsigned pte_access, int user_fault,
-		    int write_fault, int dirty, int level,
+		    int write_fault, int level,
 		    gfn_t gfn, pfn_t pfn, bool speculative,
 		    bool can_unsync, bool host_writable)
 {
 	u64 spte, entry = *sptep;
 	int ret = 0;
 
+	if (set_mmio_spte(sptep, gfn, pfn, pte_access))
+		return 0;
+
 	/*
 	 * We don't set the accessed bit, since we sometimes want to see
 	 * whether the guest actually used the pte (in order to detect
@@ -2017,8 +2199,7 @@ static int set_spte(struct kvm_vcpu *vcpu, u64 *sptep,
 	spte = PT_PRESENT_MASK;
 	if (!speculative)
 		spte |= shadow_accessed_mask;
-	if (!dirty)
-		pte_access &= ~ACC_WRITE_MASK;
+
 	if (pte_access & ACC_EXEC_MASK)
 		spte |= shadow_x_mask;
 	else
@@ -2045,15 +2226,24 @@ static int set_spte(struct kvm_vcpu *vcpu, u64 *sptep,
 		if (level > PT_PAGE_TABLE_LEVEL &&
 		    has_wrprotected_page(vcpu->kvm, gfn, level)) {
 			ret = 1;
-			drop_spte(vcpu->kvm, sptep, shadow_trap_nonpresent_pte);
+			drop_spte(vcpu->kvm, sptep);
 			goto done;
 		}
 
 		spte |= PT_WRITABLE_MASK;
 
 		if (!vcpu->arch.mmu.direct_map
-		    && !(pte_access & ACC_WRITE_MASK))
+		    && !(pte_access & ACC_WRITE_MASK)) {
 			spte &= ~PT_USER_MASK;
+			/*
+			 * If we converted a user page to a kernel page,
+			 * so that the kernel can write to it when cr0.wp=0,
+			 * then we should prevent the kernel from executing it
+			 * if SMEP is enabled.
+			 */
+			if (kvm_read_cr4_bits(vcpu, X86_CR4_SMEP))
+				spte |= PT64_NX_MASK;
+		}
 
 		/*
 		 * Optimization: for pte sync, if spte was writable the hash
@@ -2078,7 +2268,7 @@ static int set_spte(struct kvm_vcpu *vcpu, u64 *sptep,
 		mark_page_dirty(vcpu->kvm, gfn);
 
 set_pte:
-	update_spte(sptep, spte);
+	mmu_spte_update(sptep, spte);
 	/*
 	 * If we overwrite a writable spte with a read-only one we
 	 * should flush remote TLBs. Otherwise rmap_write_protect
@@ -2093,8 +2283,8 @@ done:
 
 static void mmu_set_spte(struct kvm_vcpu *vcpu, u64 *sptep,
 			 unsigned pt_access, unsigned pte_access,
-			 int user_fault, int write_fault, int dirty,
-			 int *ptwrite, int level, gfn_t gfn,
+			 int user_fault, int write_fault,
+			 int *emulate, int level, gfn_t gfn,
 			 pfn_t pfn, bool speculative,
 			 bool host_writable)
 {
@@ -2117,26 +2307,28 @@ static void mmu_set_spte(struct kvm_vcpu *vcpu, u64 *sptep,
 			u64 pte = *sptep;
 
 			child = page_header(pte & PT64_BASE_ADDR_MASK);
-			mmu_page_remove_parent_pte(child, sptep);
-			__set_spte(sptep, shadow_trap_nonpresent_pte);
+			drop_parent_pte(child, sptep);
 			kvm_flush_remote_tlbs(vcpu->kvm);
 		} else if (pfn != spte_to_pfn(*sptep)) {
 			pgprintk("hfn old %llx new %llx\n",
 				 spte_to_pfn(*sptep), pfn);
-			drop_spte(vcpu->kvm, sptep, shadow_trap_nonpresent_pte);
+			drop_spte(vcpu->kvm, sptep);
 			kvm_flush_remote_tlbs(vcpu->kvm);
 		} else
 			was_rmapped = 1;
 	}
 
 	if (set_spte(vcpu, sptep, pte_access, user_fault, write_fault,
-		      dirty, level, gfn, pfn, speculative, true,
+		      level, gfn, pfn, speculative, true,
 		      host_writable)) {
 		if (write_fault)
-			*ptwrite = 1;
+			*emulate = 1;
 		kvm_mmu_flush_tlb(vcpu);
 	}
 
+	if (unlikely(is_mmio_spte(*sptep) && emulate))
+		*emulate = 1;
+
 	pgprintk("%s: setting spte %llx\n", __func__, *sptep);
 	pgprintk("instantiating %s PTE (%s) at %llx (%llx) addr %p\n",
 		 is_large_pte(*sptep)? "2MB" : "4kB",
@@ -2145,11 +2337,13 @@ static void mmu_set_spte(struct kvm_vcpu *vcpu, u64 *sptep,
 	if (!was_rmapped && is_large_pte(*sptep))
 		++vcpu->kvm->stat.lpages;
 
-	page_header_update_slot(vcpu->kvm, sptep, gfn);
-	if (!was_rmapped) {
-		rmap_count = rmap_add(vcpu, sptep, gfn);
-		if (rmap_count > RMAP_RECYCLE_THRESHOLD)
-			rmap_recycle(vcpu, sptep, gfn);
+	if (is_shadow_present_pte(*sptep)) {
+		page_header_update_slot(vcpu->kvm, sptep, gfn);
+		if (!was_rmapped) {
+			rmap_count = rmap_add(vcpu, sptep, gfn);
+			if (rmap_count > RMAP_RECYCLE_THRESHOLD)
+				rmap_recycle(vcpu, sptep, gfn);
+		}
 	}
 	kvm_release_pfn_clean(pfn);
 	if (speculative) {
@@ -2170,8 +2364,8 @@ static pfn_t pte_prefetch_gfn_to_pfn(struct kvm_vcpu *vcpu, gfn_t gfn,
 
 	slot = gfn_to_memslot_dirty_bitmap(vcpu, gfn, no_dirty_log);
 	if (!slot) {
-		get_page(bad_page);
-		return page_to_pfn(bad_page);
+		get_page(fault_page);
+		return page_to_pfn(fault_page);
 	}
 
 	hva = gfn_to_hva_memslot(slot, gfn);
@@ -2198,7 +2392,7 @@ static int direct_pte_prefetch_many(struct kvm_vcpu *vcpu,
 
 	for (i = 0; i < ret; i++, gfn++, start++)
 		mmu_set_spte(vcpu, start, ACC_ALL,
-			     access, 0, 0, 1, NULL,
+			     access, 0, 0, NULL,
 			     sp->role.level, gfn,
 			     page_to_pfn(pages[i]), true, true);
 
@@ -2217,7 +2411,7 @@ static void __direct_pte_prefetch(struct kvm_vcpu *vcpu,
 	spte = sp->spt + i;
 
 	for (i = 0; i < PTE_PREFETCH_NUM; i++, spte++) {
-		if (*spte != shadow_trap_nonpresent_pte || spte == sptep) {
+		if (is_shadow_present_pte(*spte) || spte == sptep) {
 			if (!start)
 				continue;
 			if (direct_pte_prefetch_many(vcpu, sp, start, spte) < 0)
@@ -2254,7 +2448,7 @@ static int __direct_map(struct kvm_vcpu *vcpu, gpa_t v, int write,
 {
 	struct kvm_shadow_walk_iterator iterator;
 	struct kvm_mmu_page *sp;
-	int pt_write = 0;
+	int emulate = 0;
 	gfn_t pseudo_gfn;
 
 	for_each_shadow_entry(vcpu, (u64)gfn << PAGE_SHIFT, iterator) {
@@ -2262,14 +2456,14 @@ static int __direct_map(struct kvm_vcpu *vcpu, gpa_t v, int write,
 			unsigned pte_access = ACC_ALL;
 
 			mmu_set_spte(vcpu, iterator.sptep, ACC_ALL, pte_access,
-				     0, write, 1, &pt_write,
+				     0, write, &emulate,
 				     level, gfn, pfn, prefault, map_writable);
 			direct_pte_prefetch(vcpu, iterator.sptep);
 			++vcpu->stat.pf_fixed;
 			break;
 		}
 
-		if (*iterator.sptep == shadow_trap_nonpresent_pte) {
+		if (!is_shadow_present_pte(*iterator.sptep)) {
 			u64 base_addr = iterator.addr;
 
 			base_addr &= PT64_LVL_ADDR_MASK(iterator.level);
@@ -2283,14 +2477,14 @@ static int __direct_map(struct kvm_vcpu *vcpu, gpa_t v, int write,
 				return -ENOMEM;
 			}
 
-			__set_spte(iterator.sptep,
-				   __pa(sp->spt)
-				   | PT_PRESENT_MASK | PT_WRITABLE_MASK
-				   | shadow_user_mask | shadow_x_mask
-				   | shadow_accessed_mask);
+			mmu_spte_set(iterator.sptep,
+				     __pa(sp->spt)
+				     | PT_PRESENT_MASK | PT_WRITABLE_MASK
+				     | shadow_user_mask | shadow_x_mask
+				     | shadow_accessed_mask);
 		}
 	}
-	return pt_write;
+	return emulate;
 }
 
 static void kvm_send_hwpoison_signal(unsigned long address, struct task_struct *tsk)
@@ -2306,16 +2500,15 @@ static void kvm_send_hwpoison_signal(unsigned long address, struct task_struct *
 	send_sig_info(SIGBUS, &info, tsk);
 }
 
-static int kvm_handle_bad_page(struct kvm *kvm, gfn_t gfn, pfn_t pfn)
+static int kvm_handle_bad_page(struct kvm_vcpu *vcpu, gfn_t gfn, pfn_t pfn)
 {
 	kvm_release_pfn_clean(pfn);
 	if (is_hwpoison_pfn(pfn)) {
-		kvm_send_hwpoison_signal(gfn_to_hva(kvm, gfn), current);
+		kvm_send_hwpoison_signal(gfn_to_hva(vcpu->kvm, gfn), current);
 		return 0;
-	} else if (is_fault_pfn(pfn))
-		return -EFAULT;
+	}
 
-	return 1;
+	return -EFAULT;
 }
 
 static void transparent_hugepage_adjust(struct kvm_vcpu *vcpu,
@@ -2360,6 +2553,30 @@ static void transparent_hugepage_adjust(struct kvm_vcpu *vcpu,
 	}
 }
 
+static bool mmu_invalid_pfn(pfn_t pfn)
+{
+	return unlikely(is_invalid_pfn(pfn));
+}
+
+static bool handle_abnormal_pfn(struct kvm_vcpu *vcpu, gva_t gva, gfn_t gfn,
+				pfn_t pfn, unsigned access, int *ret_val)
+{
+	bool ret = true;
+
+	/* The pfn is invalid, report the error! */
+	if (unlikely(is_invalid_pfn(pfn))) {
+		*ret_val = kvm_handle_bad_page(vcpu, gfn, pfn);
+		goto exit;
+	}
+
+	if (unlikely(is_noslot_pfn(pfn)))
+		vcpu_cache_mmio_info(vcpu, gva, gfn, access);
+
+	ret = false;
+exit:
+	return ret;
+}
+
 static bool try_async_pf(struct kvm_vcpu *vcpu, bool prefault, gfn_t gfn,
 			 gva_t gva, pfn_t *pfn, bool write, bool *writable);
 
@@ -2394,9 +2611,8 @@ static int nonpaging_map(struct kvm_vcpu *vcpu, gva_t v, int write, gfn_t gfn,
 	if (try_async_pf(vcpu, prefault, gfn, v, &pfn, write, &map_writable))
 		return 0;
 
-	/* mmio */
-	if (is_error_pfn(pfn))
-		return kvm_handle_bad_page(vcpu->kvm, gfn, pfn);
+	if (handle_abnormal_pfn(vcpu, v, gfn, pfn, ACC_ALL, &r))
+		return r;
 
 	spin_lock(&vcpu->kvm->mmu_lock);
 	if (mmu_notifier_retry(vcpu, mmu_seq))
@@ -2623,6 +2839,7 @@ static void mmu_sync_roots(struct kvm_vcpu *vcpu)
 	if (!VALID_PAGE(vcpu->arch.mmu.root_hpa))
 		return;
 
+	vcpu_clear_mmio_info(vcpu, ~0ul);
 	trace_kvm_mmu_audit(vcpu, AUDIT_PRE_SYNC);
 	if (vcpu->arch.mmu.root_level == PT64_ROOT_LEVEL) {
 		hpa_t root = vcpu->arch.mmu.root_hpa;
@@ -2667,6 +2884,94 @@ static gpa_t nonpaging_gva_to_gpa_nested(struct kvm_vcpu *vcpu, gva_t vaddr,
 	return vcpu->arch.nested_mmu.translate_gpa(vcpu, vaddr, access);
 }
 
+static bool quickly_check_mmio_pf(struct kvm_vcpu *vcpu, u64 addr, bool direct)
+{
+	if (direct)
+		return vcpu_match_mmio_gpa(vcpu, addr);
+
+	return vcpu_match_mmio_gva(vcpu, addr);
+}
+
+
+/*
+ * On direct hosts, the last spte is only allows two states
+ * for mmio page fault:
+ *   - It is the mmio spte
+ *   - It is zapped or it is being zapped.
+ *
+ * This function completely checks the spte when the last spte
+ * is not the mmio spte.
+ */
+static bool check_direct_spte_mmio_pf(u64 spte)
+{
+	return __check_direct_spte_mmio_pf(spte);
+}
+
+static u64 walk_shadow_page_get_mmio_spte(struct kvm_vcpu *vcpu, u64 addr)
+{
+	struct kvm_shadow_walk_iterator iterator;
+	u64 spte = 0ull;
+
+	walk_shadow_page_lockless_begin(vcpu);
+	for_each_shadow_entry_lockless(vcpu, addr, iterator, spte)
+		if (!is_shadow_present_pte(spte))
+			break;
+	walk_shadow_page_lockless_end(vcpu);
+
+	return spte;
+}
+
+/*
+ * If it is a real mmio page fault, return 1 and emulat the instruction
+ * directly, return 0 to let CPU fault again on the address, -1 is
+ * returned if bug is detected.
+ */
+int handle_mmio_page_fault_common(struct kvm_vcpu *vcpu, u64 addr, bool direct)
+{
+	u64 spte;
+
+	if (quickly_check_mmio_pf(vcpu, addr, direct))
+		return 1;
+
+	spte = walk_shadow_page_get_mmio_spte(vcpu, addr);
+
+	if (is_mmio_spte(spte)) {
+		gfn_t gfn = get_mmio_spte_gfn(spte);
+		unsigned access = get_mmio_spte_access(spte);
+
+		if (direct)
+			addr = 0;
+
+		trace_handle_mmio_page_fault(addr, gfn, access);
+		vcpu_cache_mmio_info(vcpu, addr, gfn, access);
+		return 1;
+	}
+
+	/*
+	 * It's ok if the gva is remapped by other cpus on shadow guest,
+	 * it's a BUG if the gfn is not a mmio page.
+	 */
+	if (direct && !check_direct_spte_mmio_pf(spte))
+		return -1;
+
+	/*
+	 * If the page table is zapped by other cpus, let CPU fault again on
+	 * the address.
+	 */
+	return 0;
+}
+EXPORT_SYMBOL_GPL(handle_mmio_page_fault_common);
+
+static int handle_mmio_page_fault(struct kvm_vcpu *vcpu, u64 addr,
+				  u32 error_code, bool direct)
+{
+	int ret;
+
+	ret = handle_mmio_page_fault_common(vcpu, addr, direct);
+	WARN_ON(ret < 0);
+	return ret;
+}
+
 static int nonpaging_page_fault(struct kvm_vcpu *vcpu, gva_t gva,
 				u32 error_code, bool prefault)
 {
@@ -2674,6 +2979,10 @@ static int nonpaging_page_fault(struct kvm_vcpu *vcpu, gva_t gva,
 	int r;
 
 	pgprintk("%s: gva %lx error %x\n", __func__, gva, error_code);
+
+	if (unlikely(error_code & PFERR_RSVD_MASK))
+		return handle_mmio_page_fault(vcpu, gva, error_code, true);
+
 	r = mmu_topup_memory_caches(vcpu);
 	if (r)
 		return r;
@@ -2750,6 +3059,9 @@ static int tdp_page_fault(struct kvm_vcpu *vcpu, gva_t gpa, u32 error_code,
 	ASSERT(vcpu);
 	ASSERT(VALID_PAGE(vcpu->arch.mmu.root_hpa));
 
+	if (unlikely(error_code & PFERR_RSVD_MASK))
+		return handle_mmio_page_fault(vcpu, gpa, error_code, true);
+
 	r = mmu_topup_memory_caches(vcpu);
 	if (r)
 		return r;
@@ -2767,9 +3079,9 @@ static int tdp_page_fault(struct kvm_vcpu *vcpu, gva_t gpa, u32 error_code,
 	if (try_async_pf(vcpu, prefault, gfn, gpa, &pfn, write, &map_writable))
 		return 0;
 
-	/* mmio */
-	if (is_error_pfn(pfn))
-		return kvm_handle_bad_page(vcpu->kvm, gfn, pfn);
+	if (handle_abnormal_pfn(vcpu, 0, gfn, pfn, ACC_ALL, &r))
+		return r;
+
 	spin_lock(&vcpu->kvm->mmu_lock);
 	if (mmu_notifier_retry(vcpu, mmu_seq))
 		goto out_unlock;
@@ -2800,7 +3112,6 @@ static int nonpaging_init_context(struct kvm_vcpu *vcpu,
 	context->page_fault = nonpaging_page_fault;
 	context->gva_to_gpa = nonpaging_gva_to_gpa;
 	context->free = nonpaging_free;
-	context->prefetch_page = nonpaging_prefetch_page;
 	context->sync_page = nonpaging_sync_page;
 	context->invlpg = nonpaging_invlpg;
 	context->update_pte = nonpaging_update_pte;
@@ -2848,6 +3159,23 @@ static bool is_rsvd_bits_set(struct kvm_mmu *mmu, u64 gpte, int level)
 	return (gpte & mmu->rsvd_bits_mask[bit7][level-1]) != 0;
 }
 
+static bool sync_mmio_spte(u64 *sptep, gfn_t gfn, unsigned access,
+			   int *nr_present)
+{
+	if (unlikely(is_mmio_spte(*sptep))) {
+		if (gfn != get_mmio_spte_gfn(*sptep)) {
+			mmu_spte_clear_no_track(sptep);
+			return true;
+		}
+
+		(*nr_present)++;
+		mark_mmio_spte(sptep, gfn, access);
+		return true;
+	}
+
+	return false;
+}
+
 #define PTTYPE 64
 #include "paging_tmpl.h"
 #undef PTTYPE
@@ -2930,7 +3258,6 @@ static int paging64_init_context_common(struct kvm_vcpu *vcpu,
 	context->new_cr3 = paging_new_cr3;
 	context->page_fault = paging64_page_fault;
 	context->gva_to_gpa = paging64_gva_to_gpa;
-	context->prefetch_page = paging64_prefetch_page;
 	context->sync_page = paging64_sync_page;
 	context->invlpg = paging64_invlpg;
 	context->update_pte = paging64_update_pte;
@@ -2959,7 +3286,6 @@ static int paging32_init_context(struct kvm_vcpu *vcpu,
 	context->page_fault = paging32_page_fault;
 	context->gva_to_gpa = paging32_gva_to_gpa;
 	context->free = paging_free;
-	context->prefetch_page = paging32_prefetch_page;
 	context->sync_page = paging32_sync_page;
 	context->invlpg = paging32_invlpg;
 	context->update_pte = paging32_update_pte;
@@ -2984,7 +3310,6 @@ static int init_kvm_tdp_mmu(struct kvm_vcpu *vcpu)
 	context->new_cr3 = nonpaging_new_cr3;
 	context->page_fault = tdp_page_fault;
 	context->free = nonpaging_free;
-	context->prefetch_page = nonpaging_prefetch_page;
 	context->sync_page = nonpaging_sync_page;
 	context->invlpg = nonpaging_invlpg;
 	context->update_pte = nonpaging_update_pte;
@@ -3023,6 +3348,7 @@ static int init_kvm_tdp_mmu(struct kvm_vcpu *vcpu)
 int kvm_init_shadow_mmu(struct kvm_vcpu *vcpu, struct kvm_mmu *context)
 {
 	int r;
+	bool smep = kvm_read_cr4_bits(vcpu, X86_CR4_SMEP);
 	ASSERT(vcpu);
 	ASSERT(!VALID_PAGE(vcpu->arch.mmu.root_hpa));
 
@@ -3037,6 +3363,8 @@ int kvm_init_shadow_mmu(struct kvm_vcpu *vcpu, struct kvm_mmu *context)
 
 	vcpu->arch.mmu.base_role.cr4_pae = !!is_pae(vcpu);
 	vcpu->arch.mmu.base_role.cr0_wp  = is_write_protection(vcpu);
+	vcpu->arch.mmu.base_role.smep_andnot_wp
+		= smep && !is_write_protection(vcpu);
 
 	return r;
 }
@@ -3141,27 +3469,6 @@ void kvm_mmu_unload(struct kvm_vcpu *vcpu)
 }
 EXPORT_SYMBOL_GPL(kvm_mmu_unload);
 
-static void mmu_pte_write_zap_pte(struct kvm_vcpu *vcpu,
-				  struct kvm_mmu_page *sp,
-				  u64 *spte)
-{
-	u64 pte;
-	struct kvm_mmu_page *child;
-
-	pte = *spte;
-	if (is_shadow_present_pte(pte)) {
-		if (is_last_spte(pte, sp->role.level))
-			drop_spte(vcpu->kvm, spte, shadow_trap_nonpresent_pte);
-		else {
-			child = page_header(pte & PT64_BASE_ADDR_MASK);
-			mmu_page_remove_parent_pte(child, spte);
-		}
-	}
-	__set_spte(spte, shadow_trap_nonpresent_pte);
-	if (is_large_pte(pte))
-		--vcpu->kvm->stat.lpages;
-}
-
 static void mmu_pte_write_new_pte(struct kvm_vcpu *vcpu,
 				  struct kvm_mmu_page *sp, u64 *spte,
 				  const void *new)
@@ -3233,6 +3540,13 @@ void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa,
 	int level, npte, invlpg_counter, r, flooded = 0;
 	bool remote_flush, local_flush, zap_page;
 
+	/*
+	 * If we don't have indirect shadow pages, it means no page is
+	 * write-protected, so we can exit simply.
+	 */
+	if (!ACCESS_ONCE(vcpu->kvm->arch.indirect_shadow_pages))
+		return;
+
 	zap_page = remote_flush = local_flush = false;
 	offset = offset_in_page(gpa);
 
@@ -3336,7 +3650,7 @@ void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa,
 		spte = &sp->spt[page_offset / sizeof(*spte)];
 		while (npte--) {
 			entry = *spte;
-			mmu_pte_write_zap_pte(vcpu, sp, spte);
+			mmu_page_zap_pte(vcpu->kvm, sp, spte);
 			if (gentry &&
 			      !((sp->role.word ^ vcpu->arch.mmu.base_role.word)
 			      & mask.word))
@@ -3380,9 +3694,9 @@ void __kvm_mmu_free_some_pages(struct kvm_vcpu *vcpu)
 		sp = container_of(vcpu->kvm->arch.active_mmu_pages.prev,
 				  struct kvm_mmu_page, link);
 		kvm_mmu_prepare_zap_page(vcpu->kvm, sp, &invalid_list);
-		kvm_mmu_commit_zap_page(vcpu->kvm, &invalid_list);
 		++vcpu->kvm->stat.mmu_recycled;
 	}
+	kvm_mmu_commit_zap_page(vcpu->kvm, &invalid_list);
 }
 
 int kvm_mmu_page_fault(struct kvm_vcpu *vcpu, gva_t cr2, u32 error_code,
@@ -3506,15 +3820,15 @@ void kvm_mmu_slot_remove_write_access(struct kvm *kvm, int slot)
 				continue;
 
 			if (is_large_pte(pt[i])) {
-				drop_spte(kvm, &pt[i],
-					  shadow_trap_nonpresent_pte);
+				drop_spte(kvm, &pt[i]);
 				--kvm->stat.lpages;
 				continue;
 			}
 
 			/* avoid RMW */
 			if (is_writable_pte(pt[i]))
-				update_spte(&pt[i], pt[i] & ~PT_WRITABLE_MASK);
+				mmu_spte_update(&pt[i],
+						pt[i] & ~PT_WRITABLE_MASK);
 		}
 	}
 	kvm_flush_remote_tlbs(kvm);
@@ -3590,25 +3904,18 @@ static struct shrinker mmu_shrinker = {
 
 static void mmu_destroy_caches(void)
 {
-	if (pte_chain_cache)
-		kmem_cache_destroy(pte_chain_cache);
-	if (rmap_desc_cache)
-		kmem_cache_destroy(rmap_desc_cache);
+	if (pte_list_desc_cache)
+		kmem_cache_destroy(pte_list_desc_cache);
 	if (mmu_page_header_cache)
 		kmem_cache_destroy(mmu_page_header_cache);
 }
 
 int kvm_mmu_module_init(void)
 {
-	pte_chain_cache = kmem_cache_create("kvm_pte_chain",
-					    sizeof(struct kvm_pte_chain),
-					    0, 0, NULL);
-	if (!pte_chain_cache)
-		goto nomem;
-	rmap_desc_cache = kmem_cache_create("kvm_rmap_desc",
-					    sizeof(struct kvm_rmap_desc),
+	pte_list_desc_cache = kmem_cache_create("pte_list_desc",
+					    sizeof(struct pte_list_desc),
 					    0, 0, NULL);
-	if (!rmap_desc_cache)
+	if (!pte_list_desc_cache)
 		goto nomem;
 
 	mmu_page_header_cache = kmem_cache_create("kvm_mmu_page_header",
@@ -3775,16 +4082,17 @@ out:
 int kvm_mmu_get_spte_hierarchy(struct kvm_vcpu *vcpu, u64 addr, u64 sptes[4])
 {
 	struct kvm_shadow_walk_iterator iterator;
+	u64 spte;
 	int nr_sptes = 0;
 
-	spin_lock(&vcpu->kvm->mmu_lock);
-	for_each_shadow_entry(vcpu, addr, iterator) {
-		sptes[iterator.level-1] = *iterator.sptep;
+	walk_shadow_page_lockless_begin(vcpu);
+	for_each_shadow_entry_lockless(vcpu, addr, iterator, spte) {
+		sptes[iterator.level-1] = spte;
 		nr_sptes++;
-		if (!is_shadow_present_pte(*iterator.sptep))
+		if (!is_shadow_present_pte(spte))
 			break;
 	}
-	spin_unlock(&vcpu->kvm->mmu_lock);
+	walk_shadow_page_lockless_end(vcpu);
 
 	return nr_sptes;
 }
diff --git a/arch/x86/kvm/mmu.h b/arch/x86/kvm/mmu.h
index 7086ca85d3e7..e374db9af021 100644
--- a/arch/x86/kvm/mmu.h
+++ b/arch/x86/kvm/mmu.h
@@ -49,6 +49,8 @@
 #define PFERR_FETCH_MASK (1U << 4)
 
 int kvm_mmu_get_spte_hierarchy(struct kvm_vcpu *vcpu, u64 addr, u64 sptes[4]);
+void kvm_mmu_set_mmio_spte_mask(u64 mmio_mask);
+int handle_mmio_page_fault_common(struct kvm_vcpu *vcpu, u64 addr, bool direct);
 int kvm_init_shadow_mmu(struct kvm_vcpu *vcpu, struct kvm_mmu *context);
 
 static inline unsigned int kvm_mmu_available_pages(struct kvm *kvm)
@@ -76,4 +78,27 @@ static inline int is_present_gpte(unsigned long pte)
 	return pte & PT_PRESENT_MASK;
 }
 
+static inline int is_writable_pte(unsigned long pte)
+{
+	return pte & PT_WRITABLE_MASK;
+}
+
+static inline bool is_write_protection(struct kvm_vcpu *vcpu)
+{
+	return kvm_read_cr0_bits(vcpu, X86_CR0_WP);
+}
+
+static inline bool check_write_user_access(struct kvm_vcpu *vcpu,
+					   bool write_fault, bool user_fault,
+					   unsigned long pte)
+{
+	if (unlikely(write_fault && !is_writable_pte(pte)
+	      && (user_fault || is_write_protection(vcpu))))
+		return false;
+
+	if (unlikely(user_fault && !(pte & PT_USER_MASK)))
+		return false;
+
+	return true;
+}
 #endif
diff --git a/arch/x86/kvm/mmu_audit.c b/arch/x86/kvm/mmu_audit.c
index 5f6223b8bcf7..2460a265be23 100644
--- a/arch/x86/kvm/mmu_audit.c
+++ b/arch/x86/kvm/mmu_audit.c
@@ -99,18 +99,6 @@ static void audit_mappings(struct kvm_vcpu *vcpu, u64 *sptep, int level)
 				     "level = %d\n", sp, level);
 			return;
 		}
-
-		if (*sptep == shadow_notrap_nonpresent_pte) {
-			audit_printk(vcpu->kvm, "notrap spte in unsync "
-				     "sp: %p\n", sp);
-			return;
-		}
-	}
-
-	if (sp->role.direct && *sptep == shadow_notrap_nonpresent_pte) {
-		audit_printk(vcpu->kvm, "notrap spte in direct sp: %p\n",
-			     sp);
-		return;
 	}
 
 	if (!is_shadow_present_pte(*sptep) || !is_last_spte(*sptep, level))
diff --git a/arch/x86/kvm/mmutrace.h b/arch/x86/kvm/mmutrace.h
index b60b4fdb3eda..eed67f34146d 100644
--- a/arch/x86/kvm/mmutrace.h
+++ b/arch/x86/kvm/mmutrace.h
@@ -196,6 +196,54 @@ DEFINE_EVENT(kvm_mmu_page_class, kvm_mmu_prepare_zap_page,
 	TP_ARGS(sp)
 );
 
+DEFINE_EVENT(kvm_mmu_page_class, kvm_mmu_delay_free_pages,
+	TP_PROTO(struct kvm_mmu_page *sp),
+
+	TP_ARGS(sp)
+);
+
+TRACE_EVENT(
+	mark_mmio_spte,
+	TP_PROTO(u64 *sptep, gfn_t gfn, unsigned access),
+	TP_ARGS(sptep, gfn, access),
+
+	TP_STRUCT__entry(
+		__field(void *, sptep)
+		__field(gfn_t, gfn)
+		__field(unsigned, access)
+	),
+
+	TP_fast_assign(
+		__entry->sptep = sptep;
+		__entry->gfn = gfn;
+		__entry->access = access;
+	),
+
+	TP_printk("sptep:%p gfn %llx access %x", __entry->sptep, __entry->gfn,
+		  __entry->access)
+);
+
+TRACE_EVENT(
+	handle_mmio_page_fault,
+	TP_PROTO(u64 addr, gfn_t gfn, unsigned access),
+	TP_ARGS(addr, gfn, access),
+
+	TP_STRUCT__entry(
+		__field(u64, addr)
+		__field(gfn_t, gfn)
+		__field(unsigned, access)
+	),
+
+	TP_fast_assign(
+		__entry->addr = addr;
+		__entry->gfn = gfn;
+		__entry->access = access;
+	),
+
+	TP_printk("addr:%llx gfn %llx access %x", __entry->addr, __entry->gfn,
+		  __entry->access)
+);
+
 TRACE_EVENT(
 	kvm_mmu_audit,
 	TP_PROTO(struct kvm_vcpu *vcpu, int audit_point),
diff --git a/arch/x86/kvm/paging_tmpl.h b/arch/x86/kvm/paging_tmpl.h
index 9d03ad4dd5ec..507e2b844cfa 100644
--- a/arch/x86/kvm/paging_tmpl.h
+++ b/arch/x86/kvm/paging_tmpl.h
@@ -101,11 +101,15 @@ static int FNAME(cmpxchg_gpte)(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu,
 	return (ret != orig_pte);
 }
 
-static unsigned FNAME(gpte_access)(struct kvm_vcpu *vcpu, pt_element_t gpte)
+static unsigned FNAME(gpte_access)(struct kvm_vcpu *vcpu, pt_element_t gpte,
+				   bool last)
 {
 	unsigned access;
 
 	access = (gpte & (PT_WRITABLE_MASK | PT_USER_MASK)) | ACC_EXEC_MASK;
+	if (last && !is_dirty_gpte(gpte))
+		access &= ~ACC_WRITE_MASK;
+
 #if PTTYPE == 64
 	if (vcpu->arch.mmu.nx)
 		access &= ~(gpte >> PT64_NX_SHIFT);
@@ -113,6 +117,24 @@ static unsigned FNAME(gpte_access)(struct kvm_vcpu *vcpu, pt_element_t gpte)
 	return access;
 }
 
+static bool FNAME(is_last_gpte)(struct guest_walker *walker,
+				struct kvm_vcpu *vcpu, struct kvm_mmu *mmu,
+				pt_element_t gpte)
+{
+	if (walker->level == PT_PAGE_TABLE_LEVEL)
+		return true;
+
+	if ((walker->level == PT_DIRECTORY_LEVEL) && is_large_pte(gpte) &&
+	    (PTTYPE == 64 || is_pse(vcpu)))
+		return true;
+
+	if ((walker->level == PT_PDPE_LEVEL) && is_large_pte(gpte) &&
+	    (mmu->root_level == PT64_ROOT_LEVEL))
+		return true;
+
+	return false;
+}
+
 /*
  * Fetch a guest pte for a guest virtual address
  */
@@ -125,18 +147,17 @@ static int FNAME(walk_addr_generic)(struct guest_walker *walker,
 	gfn_t table_gfn;
 	unsigned index, pt_access, uninitialized_var(pte_access);
 	gpa_t pte_gpa;
-	bool eperm, present, rsvd_fault;
-	int offset, write_fault, user_fault, fetch_fault;
-
-	write_fault = access & PFERR_WRITE_MASK;
-	user_fault = access & PFERR_USER_MASK;
-	fetch_fault = access & PFERR_FETCH_MASK;
+	bool eperm;
+	int offset;
+	const int write_fault = access & PFERR_WRITE_MASK;
+	const int user_fault  = access & PFERR_USER_MASK;
+	const int fetch_fault = access & PFERR_FETCH_MASK;
+	u16 errcode = 0;
 
 	trace_kvm_mmu_pagetable_walk(addr, write_fault, user_fault,
 				     fetch_fault);
-walk:
-	present = true;
-	eperm = rsvd_fault = false;
+retry_walk:
+	eperm = false;
 	walker->level = mmu->root_level;
 	pte           = mmu->get_cr3(vcpu);
 
@@ -144,10 +165,8 @@ walk:
 	if (walker->level == PT32E_ROOT_LEVEL) {
 		pte = kvm_pdptr_read_mmu(vcpu, mmu, (addr >> 30) & 3);
 		trace_kvm_mmu_paging_element(pte, walker->level);
-		if (!is_present_gpte(pte)) {
-			present = false;
+		if (!is_present_gpte(pte))
 			goto error;
-		}
 		--walker->level;
 	}
 #endif
@@ -170,42 +189,31 @@ walk:
 
 		real_gfn = mmu->translate_gpa(vcpu, gfn_to_gpa(table_gfn),
 					      PFERR_USER_MASK|PFERR_WRITE_MASK);
-		if (unlikely(real_gfn == UNMAPPED_GVA)) {
-			present = false;
-			break;
-		}
+		if (unlikely(real_gfn == UNMAPPED_GVA))
+			goto error;
 		real_gfn = gpa_to_gfn(real_gfn);
 
 		host_addr = gfn_to_hva(vcpu->kvm, real_gfn);
-		if (unlikely(kvm_is_error_hva(host_addr))) {
-			present = false;
-			break;
-		}
+		if (unlikely(kvm_is_error_hva(host_addr)))
+			goto error;
 
 		ptep_user = (pt_element_t __user *)((void *)host_addr + offset);
-		if (unlikely(__copy_from_user(&pte, ptep_user, sizeof(pte)))) {
-			present = false;
-			break;
-		}
+		if (unlikely(__copy_from_user(&pte, ptep_user, sizeof(pte))))
+			goto error;
 
 		trace_kvm_mmu_paging_element(pte, walker->level);
 
-		if (unlikely(!is_present_gpte(pte))) {
-			present = false;
-			break;
-		}
+		if (unlikely(!is_present_gpte(pte)))
+			goto error;
 
 		if (unlikely(is_rsvd_bits_set(&vcpu->arch.mmu, pte,
 					      walker->level))) {
-			rsvd_fault = true;
-			break;
+			errcode |= PFERR_RSVD_MASK | PFERR_PRESENT_MASK;
+			goto error;
 		}
 
-		if (unlikely(write_fault && !is_writable_pte(pte)
-			     && (user_fault || is_write_protection(vcpu))))
-			eperm = true;
-
-		if (unlikely(user_fault && !(pte & PT_USER_MASK)))
+		if (!check_write_user_access(vcpu, write_fault, user_fault,
+					  pte))
 			eperm = true;
 
 #if PTTYPE == 64
@@ -213,39 +221,35 @@ walk:
 			eperm = true;
 #endif
 
-		if (!eperm && !rsvd_fault
-		    && unlikely(!(pte & PT_ACCESSED_MASK))) {
+		if (!eperm && unlikely(!(pte & PT_ACCESSED_MASK))) {
 			int ret;
 			trace_kvm_mmu_set_accessed_bit(table_gfn, index,
 						       sizeof(pte));
 			ret = FNAME(cmpxchg_gpte)(vcpu, mmu, ptep_user, index,
 						  pte, pte|PT_ACCESSED_MASK);
-			if (unlikely(ret < 0)) {
-				present = false;
-				break;
-			} else if (ret)
-				goto walk;
+			if (unlikely(ret < 0))
+				goto error;
+			else if (ret)
+				goto retry_walk;
 
 			mark_page_dirty(vcpu->kvm, table_gfn);
 			pte |= PT_ACCESSED_MASK;
 		}
 
-		pte_access = pt_access & FNAME(gpte_access)(vcpu, pte);
-
 		walker->ptes[walker->level - 1] = pte;
 
-		if ((walker->level == PT_PAGE_TABLE_LEVEL) ||
-		    ((walker->level == PT_DIRECTORY_LEVEL) &&
-				is_large_pte(pte) &&
-				(PTTYPE == 64 || is_pse(vcpu))) ||
-		    ((walker->level == PT_PDPE_LEVEL) &&
-				is_large_pte(pte) &&
-				mmu->root_level == PT64_ROOT_LEVEL)) {
+		if (FNAME(is_last_gpte)(walker, vcpu, mmu, pte)) {
 			int lvl = walker->level;
 			gpa_t real_gpa;
 			gfn_t gfn;
 			u32 ac;
 
+			/* check if the kernel is fetching from user page */
+			if (unlikely(pte_access & PT_USER_MASK) &&
+			    kvm_read_cr4_bits(vcpu, X86_CR4_SMEP))
+				if (fetch_fault && !user_fault)
+					eperm = true;
+
 			gfn = gpte_to_gfn_lvl(pte, lvl);
 			gfn += (addr & PT_LVL_OFFSET_MASK(lvl)) >> PAGE_SHIFT;
 
@@ -266,12 +270,14 @@ walk:
 			break;
 		}
 
-		pt_access = pte_access;
+		pt_access &= FNAME(gpte_access)(vcpu, pte, false);
 		--walker->level;
 	}
 
-	if (unlikely(!present || eperm || rsvd_fault))
+	if (unlikely(eperm)) {
+		errcode |= PFERR_PRESENT_MASK;
 		goto error;
+	}
 
 	if (write_fault && unlikely(!is_dirty_gpte(pte))) {
 		int ret;
@@ -279,17 +285,17 @@ walk:
 		trace_kvm_mmu_set_dirty_bit(table_gfn, index, sizeof(pte));
 		ret = FNAME(cmpxchg_gpte)(vcpu, mmu, ptep_user, index,
 					  pte, pte|PT_DIRTY_MASK);
-		if (unlikely(ret < 0)) {
-			present = false;
+		if (unlikely(ret < 0))
 			goto error;
-		} else if (ret)
-			goto walk;
+		else if (ret)
+			goto retry_walk;
 
 		mark_page_dirty(vcpu->kvm, table_gfn);
 		pte |= PT_DIRTY_MASK;
 		walker->ptes[walker->level - 1] = pte;
 	}
 
+	pte_access = pt_access & FNAME(gpte_access)(vcpu, pte, true);
 	walker->pt_access = pt_access;
 	walker->pte_access = pte_access;
 	pgprintk("%s: pte %llx pte_access %x pt_access %x\n",
@@ -297,19 +303,14 @@ walk:
 	return 1;
 
 error:
+	errcode |= write_fault | user_fault;
+	if (fetch_fault && (mmu->nx ||
+			    kvm_read_cr4_bits(vcpu, X86_CR4_SMEP)))
+		errcode |= PFERR_FETCH_MASK;
+
 	walker->fault.vector = PF_VECTOR;
 	walker->fault.error_code_valid = true;
-	walker->fault.error_code = 0;
-	if (present)
-		walker->fault.error_code |= PFERR_PRESENT_MASK;
-
-	walker->fault.error_code |= write_fault | user_fault;
-
-	if (fetch_fault && mmu->nx)
-		walker->fault.error_code |= PFERR_FETCH_MASK;
-	if (rsvd_fault)
-		walker->fault.error_code |= PFERR_RSVD_MASK;
-
+	walker->fault.error_code = errcode;
 	walker->fault.address = addr;
 	walker->fault.nested_page_fault = mmu != vcpu->arch.walk_mmu;
 
@@ -336,16 +337,11 @@ static bool FNAME(prefetch_invalid_gpte)(struct kvm_vcpu *vcpu,
 				    struct kvm_mmu_page *sp, u64 *spte,
 				    pt_element_t gpte)
 {
-	u64 nonpresent = shadow_trap_nonpresent_pte;
-
 	if (is_rsvd_bits_set(&vcpu->arch.mmu, gpte, PT_PAGE_TABLE_LEVEL))
 		goto no_present;
 
-	if (!is_present_gpte(gpte)) {
-		if (!sp->unsync)
-			nonpresent = shadow_notrap_nonpresent_pte;
+	if (!is_present_gpte(gpte))
 		goto no_present;
-	}
 
 	if (!(gpte & PT_ACCESSED_MASK))
 		goto no_present;
@@ -353,7 +349,7 @@ static bool FNAME(prefetch_invalid_gpte)(struct kvm_vcpu *vcpu,
 	return false;
 
 no_present:
-	drop_spte(vcpu->kvm, spte, nonpresent);
+	drop_spte(vcpu->kvm, spte);
 	return true;
 }
 
@@ -369,9 +365,9 @@ static void FNAME(update_pte)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp,
 		return;
 
 	pgprintk("%s: gpte %llx spte %p\n", __func__, (u64)gpte, spte);
-	pte_access = sp->role.access & FNAME(gpte_access)(vcpu, gpte);
+	pte_access = sp->role.access & FNAME(gpte_access)(vcpu, gpte, true);
 	pfn = gfn_to_pfn_atomic(vcpu->kvm, gpte_to_gfn(gpte));
-	if (is_error_pfn(pfn)) {
+	if (mmu_invalid_pfn(pfn)) {
 		kvm_release_pfn_clean(pfn);
 		return;
 	}
@@ -381,7 +377,7 @@ static void FNAME(update_pte)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp,
 	 * vcpu->arch.update_pte.pfn was fetched from get_user_pages(write = 1).
 	 */
 	mmu_set_spte(vcpu, spte, sp->role.access, pte_access, 0, 0,
-		     is_dirty_gpte(gpte), NULL, PT_PAGE_TABLE_LEVEL,
+		     NULL, PT_PAGE_TABLE_LEVEL,
 		     gpte_to_gfn(gpte), pfn, true, true);
 }
 
@@ -432,12 +428,11 @@ static void FNAME(pte_prefetch)(struct kvm_vcpu *vcpu, struct guest_walker *gw,
 		unsigned pte_access;
 		gfn_t gfn;
 		pfn_t pfn;
-		bool dirty;
 
 		if (spte == sptep)
 			continue;
 
-		if (*spte != shadow_trap_nonpresent_pte)
+		if (is_shadow_present_pte(*spte))
 			continue;
 
 		gpte = gptep[i];
@@ -445,18 +440,18 @@ static void FNAME(pte_prefetch)(struct kvm_vcpu *vcpu, struct guest_walker *gw,
 		if (FNAME(prefetch_invalid_gpte)(vcpu, sp, spte, gpte))
 			continue;
 
-		pte_access = sp->role.access & FNAME(gpte_access)(vcpu, gpte);
+		pte_access = sp->role.access & FNAME(gpte_access)(vcpu, gpte,
+								  true);
 		gfn = gpte_to_gfn(gpte);
-		dirty = is_dirty_gpte(gpte);
 		pfn = pte_prefetch_gfn_to_pfn(vcpu, gfn,
-				      (pte_access & ACC_WRITE_MASK) && dirty);
-		if (is_error_pfn(pfn)) {
+				      pte_access & ACC_WRITE_MASK);
+		if (mmu_invalid_pfn(pfn)) {
 			kvm_release_pfn_clean(pfn);
 			break;
 		}
 
 		mmu_set_spte(vcpu, spte, sp->role.access, pte_access, 0, 0,
-			     dirty, NULL, PT_PAGE_TABLE_LEVEL, gfn,
+			     NULL, PT_PAGE_TABLE_LEVEL, gfn,
 			     pfn, true, true);
 	}
 }
@@ -467,12 +462,11 @@ static void FNAME(pte_prefetch)(struct kvm_vcpu *vcpu, struct guest_walker *gw,
 static u64 *FNAME(fetch)(struct kvm_vcpu *vcpu, gva_t addr,
 			 struct guest_walker *gw,
 			 int user_fault, int write_fault, int hlevel,
-			 int *ptwrite, pfn_t pfn, bool map_writable,
+			 int *emulate, pfn_t pfn, bool map_writable,
 			 bool prefault)
 {
 	unsigned access = gw->pt_access;
 	struct kvm_mmu_page *sp = NULL;
-	bool dirty = is_dirty_gpte(gw->ptes[gw->level - 1]);
 	int top_level;
 	unsigned direct_access;
 	struct kvm_shadow_walk_iterator it;
@@ -480,9 +474,7 @@ static u64 *FNAME(fetch)(struct kvm_vcpu *vcpu, gva_t addr,
 	if (!is_present_gpte(gw->ptes[gw->level - 1]))
 		return NULL;
 
-	direct_access = gw->pt_access & gw->pte_access;
-	if (!dirty)
-		direct_access &= ~ACC_WRITE_MASK;
+	direct_access = gw->pte_access;
 
 	top_level = vcpu->arch.mmu.root_level;
 	if (top_level == PT32E_ROOT_LEVEL)
@@ -540,8 +532,8 @@ static u64 *FNAME(fetch)(struct kvm_vcpu *vcpu, gva_t addr,
 		link_shadow_page(it.sptep, sp);
 	}
 
-	mmu_set_spte(vcpu, it.sptep, access, gw->pte_access & access,
-		     user_fault, write_fault, dirty, ptwrite, it.level,
+	mmu_set_spte(vcpu, it.sptep, access, gw->pte_access,
+		     user_fault, write_fault, emulate, it.level,
 		     gw->gfn, pfn, prefault, map_writable);
 	FNAME(pte_prefetch)(vcpu, gw, it.sptep);
 
@@ -575,7 +567,7 @@ static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gva_t addr, u32 error_code,
 	int user_fault = error_code & PFERR_USER_MASK;
 	struct guest_walker walker;
 	u64 *sptep;
-	int write_pt = 0;
+	int emulate = 0;
 	int r;
 	pfn_t pfn;
 	int level = PT_PAGE_TABLE_LEVEL;
@@ -585,6 +577,10 @@ static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gva_t addr, u32 error_code,
 
 	pgprintk("%s: addr %lx err %x\n", __func__, addr, error_code);
 
+	if (unlikely(error_code & PFERR_RSVD_MASK))
+		return handle_mmio_page_fault(vcpu, addr, error_code,
+					      mmu_is_nested(vcpu));
+
 	r = mmu_topup_memory_caches(vcpu);
 	if (r)
 		return r;
@@ -623,9 +619,9 @@ static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gva_t addr, u32 error_code,
 			 &map_writable))
 		return 0;
 
-	/* mmio */
-	if (is_error_pfn(pfn))
-		return kvm_handle_bad_page(vcpu->kvm, walker.gfn, pfn);
+	if (handle_abnormal_pfn(vcpu, mmu_is_nested(vcpu) ? 0 : addr,
+				walker.gfn, pfn, walker.pte_access, &r))
+		return r;
 
 	spin_lock(&vcpu->kvm->mmu_lock);
 	if (mmu_notifier_retry(vcpu, mmu_seq))
@@ -636,19 +632,19 @@ static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gva_t addr, u32 error_code,
 	if (!force_pt_level)
 		transparent_hugepage_adjust(vcpu, &walker.gfn, &pfn, &level);
 	sptep = FNAME(fetch)(vcpu, addr, &walker, user_fault, write_fault,
-			     level, &write_pt, pfn, map_writable, prefault);
+			     level, &emulate, pfn, map_writable, prefault);
 	(void)sptep;
-	pgprintk("%s: shadow pte %p %llx ptwrite %d\n", __func__,
-		 sptep, *sptep, write_pt);
+	pgprintk("%s: shadow pte %p %llx emulate %d\n", __func__,
+		 sptep, *sptep, emulate);
 
-	if (!write_pt)
+	if (!emulate)
 		vcpu->arch.last_pt_write_count = 0; /* reset fork detector */
 
 	++vcpu->stat.pf_fixed;
 	trace_kvm_mmu_audit(vcpu, AUDIT_POST_PAGE_FAULT);
 	spin_unlock(&vcpu->kvm->mmu_lock);
 
-	return write_pt;
+	return emulate;
 
 out_unlock:
 	spin_unlock(&vcpu->kvm->mmu_lock);
@@ -665,6 +661,8 @@ static void FNAME(invlpg)(struct kvm_vcpu *vcpu, gva_t gva)
 	u64 *sptep;
 	int need_flush = 0;
 
+	vcpu_clear_mmio_info(vcpu, gva);
+
 	spin_lock(&vcpu->kvm->mmu_lock);
 
 	for_each_shadow_entry(vcpu, gva, iterator) {
@@ -688,11 +686,11 @@ static void FNAME(invlpg)(struct kvm_vcpu *vcpu, gva_t gva)
 			if (is_shadow_present_pte(*sptep)) {
 				if (is_large_pte(*sptep))
 					--vcpu->kvm->stat.lpages;
-				drop_spte(vcpu->kvm, sptep,
-					  shadow_trap_nonpresent_pte);
+				drop_spte(vcpu->kvm, sptep);
 				need_flush = 1;
-			} else
-				__set_spte(sptep, shadow_trap_nonpresent_pte);
+			} else if (is_mmio_spte(*sptep))
+				mmu_spte_clear_no_track(sptep);
+
 			break;
 		}
 
@@ -752,36 +750,6 @@ static gpa_t FNAME(gva_to_gpa_nested)(struct kvm_vcpu *vcpu, gva_t vaddr,
 	return gpa;
 }
 
-static void FNAME(prefetch_page)(struct kvm_vcpu *vcpu,
-				 struct kvm_mmu_page *sp)
-{
-	int i, j, offset, r;
-	pt_element_t pt[256 / sizeof(pt_element_t)];
-	gpa_t pte_gpa;
-
-	if (sp->role.direct
-	    || (PTTYPE == 32 && sp->role.level > PT_PAGE_TABLE_LEVEL)) {
-		nonpaging_prefetch_page(vcpu, sp);
-		return;
-	}
-
-	pte_gpa = gfn_to_gpa(sp->gfn);
-	if (PTTYPE == 32) {
-		offset = sp->role.quadrant << PT64_LEVEL_BITS;
-		pte_gpa += offset * sizeof(pt_element_t);
-	}
-
-	for (i = 0; i < PT64_ENT_PER_PAGE; i += ARRAY_SIZE(pt)) {
-		r = kvm_read_guest_atomic(vcpu->kvm, pte_gpa, pt, sizeof pt);
-		pte_gpa += ARRAY_SIZE(pt) * sizeof(pt_element_t);
-		for (j = 0; j < ARRAY_SIZE(pt); ++j)
-			if (r || is_present_gpte(pt[j]))
-				sp->spt[i+j] = shadow_trap_nonpresent_pte;
-			else
-				sp->spt[i+j] = shadow_notrap_nonpresent_pte;
-	}
-}
-
 /*
  * Using the cached information from sp->gfns is safe because:
  * - The spte has a reference to the struct page, so the pfn for a given gfn
@@ -817,7 +785,7 @@ static int FNAME(sync_page)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp)
 		gpa_t pte_gpa;
 		gfn_t gfn;
 
-		if (!is_shadow_present_pte(sp->spt[i]))
+		if (!sp->spt[i])
 			continue;
 
 		pte_gpa = first_pte_gpa + i * sizeof(pt_element_t);
@@ -826,26 +794,30 @@ static int FNAME(sync_page)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp)
 					  sizeof(pt_element_t)))
 			return -EINVAL;
 
-		gfn = gpte_to_gfn(gpte);
-
 		if (FNAME(prefetch_invalid_gpte)(vcpu, sp, &sp->spt[i], gpte)) {
 			vcpu->kvm->tlbs_dirty++;
 			continue;
 		}
 
+		gfn = gpte_to_gfn(gpte);
+		pte_access = sp->role.access;
+		pte_access &= FNAME(gpte_access)(vcpu, gpte, true);
+
+		if (sync_mmio_spte(&sp->spt[i], gfn, pte_access, &nr_present))
+			continue;
+
 		if (gfn != sp->gfns[i]) {
-			drop_spte(vcpu->kvm, &sp->spt[i],
-				      shadow_trap_nonpresent_pte);
+			drop_spte(vcpu->kvm, &sp->spt[i]);
 			vcpu->kvm->tlbs_dirty++;
 			continue;
 		}
 
 		nr_present++;
-		pte_access = sp->role.access & FNAME(gpte_access)(vcpu, gpte);
+
 		host_writable = sp->spt[i] & SPTE_HOST_WRITEABLE;
 
 		set_spte(vcpu, &sp->spt[i], pte_access, 0, 0,
-			 is_dirty_gpte(gpte), PT_PAGE_TABLE_LEVEL, gfn,
+			 PT_PAGE_TABLE_LEVEL, gfn,
 			 spte_to_pfn(sp->spt[i]), true, false,
 			 host_writable);
 	}
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 506e4fe23adc..475d1c948501 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -1496,11 +1496,14 @@ static void svm_set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0)
 	update_cr0_intercept(svm);
 }
 
-static void svm_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4)
+static int svm_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4)
 {
 	unsigned long host_cr4_mce = read_cr4() & X86_CR4_MCE;
 	unsigned long old_cr4 = to_svm(vcpu)->vmcb->save.cr4;
 
+	if (cr4 & X86_CR4_VMXE)
+		return 1;
+
 	if (npt_enabled && ((old_cr4 ^ cr4) & X86_CR4_PGE))
 		svm_flush_tlb(vcpu);
 
@@ -1510,6 +1513,7 @@ static void svm_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4)
 	cr4 |= host_cr4_mce;
 	to_svm(vcpu)->vmcb->save.cr4 = cr4;
 	mark_dirty(to_svm(vcpu)->vmcb, VMCB_CR);
+	return 0;
 }
 
 static void svm_set_segment(struct kvm_vcpu *vcpu,
diff --git a/arch/x86/kvm/trace.h b/arch/x86/kvm/trace.h
index db932760ea82..3ff898c104f7 100644
--- a/arch/x86/kvm/trace.h
+++ b/arch/x86/kvm/trace.h
@@ -675,12 +675,12 @@ TRACE_EVENT(kvm_emulate_insn,
 		),
 
 	TP_fast_assign(
-		__entry->rip = vcpu->arch.emulate_ctxt.decode.fetch.start;
+		__entry->rip = vcpu->arch.emulate_ctxt.fetch.start;
 		__entry->csbase = kvm_x86_ops->get_segment_base(vcpu, VCPU_SREG_CS);
-		__entry->len = vcpu->arch.emulate_ctxt.decode.eip
-			       - vcpu->arch.emulate_ctxt.decode.fetch.start;
+		__entry->len = vcpu->arch.emulate_ctxt._eip
+			       - vcpu->arch.emulate_ctxt.fetch.start;
 		memcpy(__entry->insn,
-		       vcpu->arch.emulate_ctxt.decode.fetch.data,
+		       vcpu->arch.emulate_ctxt.fetch.data,
 		       15);
 		__entry->flags = kei_decode_mode(vcpu->arch.emulate_ctxt.mode);
 		__entry->failed = failed;
@@ -698,6 +698,29 @@ TRACE_EVENT(kvm_emulate_insn,
 #define trace_kvm_emulate_insn_start(vcpu) trace_kvm_emulate_insn(vcpu, 0)
 #define trace_kvm_emulate_insn_failed(vcpu) trace_kvm_emulate_insn(vcpu, 1)
 
+TRACE_EVENT(
+	vcpu_match_mmio,
+	TP_PROTO(gva_t gva, gpa_t gpa, bool write, bool gpa_match),
+	TP_ARGS(gva, gpa, write, gpa_match),
+
+	TP_STRUCT__entry(
+		__field(gva_t, gva)
+		__field(gpa_t, gpa)
+		__field(bool, write)
+		__field(bool, gpa_match)
+		),
+
+	TP_fast_assign(
+		__entry->gva = gva;
+		__entry->gpa = gpa;
+		__entry->write = write;
+		__entry->gpa_match = gpa_match
+		),
+
+	TP_printk("gva %#lx gpa %#llx %s %s", __entry->gva, __entry->gpa,
+		  __entry->write ? "Write" : "Read",
+		  __entry->gpa_match ? "GPA" : "GVA")
+);
 #endif /* _TRACE_KVM_H */
 
 #undef TRACE_INCLUDE_PATH
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index d48ec60ea421..e65a158dee64 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -43,13 +43,12 @@
 #include "trace.h"
 
 #define __ex(x) __kvm_handle_fault_on_reboot(x)
+#define __ex_clear(x, reg) \
+	____kvm_handle_fault_on_reboot(x, "xor " reg " , " reg)
 
 MODULE_AUTHOR("Qumranet");
 MODULE_LICENSE("GPL");
 
-static int __read_mostly bypass_guest_pf = 1;
-module_param(bypass_guest_pf, bool, S_IRUGO);
-
 static int __read_mostly enable_vpid = 1;
 module_param_named(vpid, enable_vpid, bool, 0444);
 
@@ -72,6 +71,14 @@ module_param(vmm_exclusive, bool, S_IRUGO);
 static int __read_mostly yield_on_hlt = 1;
 module_param(yield_on_hlt, bool, S_IRUGO);
 
+/*
+ * If nested=1, nested virtualization is supported, i.e., guests may use
+ * VMX and be a hypervisor for its own guests. If nested=0, guests may not
+ * use VMX instructions.
+ */
+static int __read_mostly nested = 0;
+module_param(nested, bool, S_IRUGO);
+
 #define KVM_GUEST_CR0_MASK_UNRESTRICTED_GUEST				\
 	(X86_CR0_WP | X86_CR0_NE | X86_CR0_NW | X86_CR0_CD)
 #define KVM_GUEST_CR0_MASK						\
@@ -109,6 +116,7 @@ static int ple_window = KVM_VMX_DEFAULT_PLE_WINDOW;
 module_param(ple_window, int, S_IRUGO);
 
 #define NR_AUTOLOAD_MSRS 1
+#define VMCS02_POOL_SIZE 1
 
 struct vmcs {
 	u32 revision_id;
@@ -116,17 +124,237 @@ struct vmcs {
 	char data[0];
 };
 
+/*
+ * Track a VMCS that may be loaded on a certain CPU. If it is (cpu!=-1), also
+ * remember whether it was VMLAUNCHed, and maintain a linked list of all VMCSs
+ * loaded on this CPU (so we can clear them if the CPU goes down).
+ */
+struct loaded_vmcs {
+	struct vmcs *vmcs;
+	int cpu;
+	int launched;
+	struct list_head loaded_vmcss_on_cpu_link;
+};
+
 struct shared_msr_entry {
 	unsigned index;
 	u64 data;
 	u64 mask;
 };
 
+/*
+ * struct vmcs12 describes the state that our guest hypervisor (L1) keeps for a
+ * single nested guest (L2), hence the name vmcs12. Any VMX implementation has
+ * a VMCS structure, and vmcs12 is our emulated VMX's VMCS. This structure is
+ * stored in guest memory specified by VMPTRLD, but is opaque to the guest,
+ * which must access it using VMREAD/VMWRITE/VMCLEAR instructions.
+ * More than one of these structures may exist, if L1 runs multiple L2 guests.
+ * nested_vmx_run() will use the data here to build a vmcs02: a VMCS for the
+ * underlying hardware which will be used to run L2.
+ * This structure is packed to ensure that its layout is identical across
+ * machines (necessary for live migration).
+ * If there are changes in this struct, VMCS12_REVISION must be changed.
+ */
+typedef u64 natural_width;
+struct __packed vmcs12 {
+	/* According to the Intel spec, a VMCS region must start with the
+	 * following two fields. Then follow implementation-specific data.
+	 */
+	u32 revision_id;
+	u32 abort;
+
+	u32 launch_state; /* set to 0 by VMCLEAR, to 1 by VMLAUNCH */
+	u32 padding[7]; /* room for future expansion */
+
+	u64 io_bitmap_a;
+	u64 io_bitmap_b;
+	u64 msr_bitmap;
+	u64 vm_exit_msr_store_addr;
+	u64 vm_exit_msr_load_addr;
+	u64 vm_entry_msr_load_addr;
+	u64 tsc_offset;
+	u64 virtual_apic_page_addr;
+	u64 apic_access_addr;
+	u64 ept_pointer;
+	u64 guest_physical_address;
+	u64 vmcs_link_pointer;
+	u64 guest_ia32_debugctl;
+	u64 guest_ia32_pat;
+	u64 guest_ia32_efer;
+	u64 guest_ia32_perf_global_ctrl;
+	u64 guest_pdptr0;
+	u64 guest_pdptr1;
+	u64 guest_pdptr2;
+	u64 guest_pdptr3;
+	u64 host_ia32_pat;
+	u64 host_ia32_efer;
+	u64 host_ia32_perf_global_ctrl;
+	u64 padding64[8]; /* room for future expansion */
+	/*
+	 * To allow migration of L1 (complete with its L2 guests) between
+	 * machines of different natural widths (32 or 64 bit), we cannot have
+	 * unsigned long fields with no explict size. We use u64 (aliased
+	 * natural_width) instead. Luckily, x86 is little-endian.
+	 */
+	natural_width cr0_guest_host_mask;
+	natural_width cr4_guest_host_mask;
+	natural_width cr0_read_shadow;
+	natural_width cr4_read_shadow;
+	natural_width cr3_target_value0;
+	natural_width cr3_target_value1;
+	natural_width cr3_target_value2;
+	natural_width cr3_target_value3;
+	natural_width exit_qualification;
+	natural_width guest_linear_address;
+	natural_width guest_cr0;
+	natural_width guest_cr3;
+	natural_width guest_cr4;
+	natural_width guest_es_base;
+	natural_width guest_cs_base;
+	natural_width guest_ss_base;
+	natural_width guest_ds_base;
+	natural_width guest_fs_base;
+	natural_width guest_gs_base;
+	natural_width guest_ldtr_base;
+	natural_width guest_tr_base;
+	natural_width guest_gdtr_base;
+	natural_width guest_idtr_base;
+	natural_width guest_dr7;
+	natural_width guest_rsp;
+	natural_width guest_rip;
+	natural_width guest_rflags;
+	natural_width guest_pending_dbg_exceptions;
+	natural_width guest_sysenter_esp;
+	natural_width guest_sysenter_eip;
+	natural_width host_cr0;
+	natural_width host_cr3;
+	natural_width host_cr4;
+	natural_width host_fs_base;
+	natural_width host_gs_base;
+	natural_width host_tr_base;
+	natural_width host_gdtr_base;
+	natural_width host_idtr_base;
+	natural_width host_ia32_sysenter_esp;
+	natural_width host_ia32_sysenter_eip;
+	natural_width host_rsp;
+	natural_width host_rip;
+	natural_width paddingl[8]; /* room for future expansion */
+	u32 pin_based_vm_exec_control;
+	u32 cpu_based_vm_exec_control;
+	u32 exception_bitmap;
+	u32 page_fault_error_code_mask;
+	u32 page_fault_error_code_match;
+	u32 cr3_target_count;
+	u32 vm_exit_controls;
+	u32 vm_exit_msr_store_count;
+	u32 vm_exit_msr_load_count;
+	u32 vm_entry_controls;
+	u32 vm_entry_msr_load_count;
+	u32 vm_entry_intr_info_field;
+	u32 vm_entry_exception_error_code;
+	u32 vm_entry_instruction_len;
+	u32 tpr_threshold;
+	u32 secondary_vm_exec_control;
+	u32 vm_instruction_error;
+	u32 vm_exit_reason;
+	u32 vm_exit_intr_info;
+	u32 vm_exit_intr_error_code;
+	u32 idt_vectoring_info_field;
+	u32 idt_vectoring_error_code;
+	u32 vm_exit_instruction_len;
+	u32 vmx_instruction_info;
+	u32 guest_es_limit;
+	u32 guest_cs_limit;
+	u32 guest_ss_limit;
+	u32 guest_ds_limit;
+	u32 guest_fs_limit;
+	u32 guest_gs_limit;
+	u32 guest_ldtr_limit;
+	u32 guest_tr_limit;
+	u32 guest_gdtr_limit;
+	u32 guest_idtr_limit;
+	u32 guest_es_ar_bytes;
+	u32 guest_cs_ar_bytes;
+	u32 guest_ss_ar_bytes;
+	u32 guest_ds_ar_bytes;
+	u32 guest_fs_ar_bytes;
+	u32 guest_gs_ar_bytes;
+	u32 guest_ldtr_ar_bytes;
+	u32 guest_tr_ar_bytes;
+	u32 guest_interruptibility_info;
+	u32 guest_activity_state;
+	u32 guest_sysenter_cs;
+	u32 host_ia32_sysenter_cs;
+	u32 padding32[8]; /* room for future expansion */
+	u16 virtual_processor_id;
+	u16 guest_es_selector;
+	u16 guest_cs_selector;
+	u16 guest_ss_selector;
+	u16 guest_ds_selector;
+	u16 guest_fs_selector;
+	u16 guest_gs_selector;
+	u16 guest_ldtr_selector;
+	u16 guest_tr_selector;
+	u16 host_es_selector;
+	u16 host_cs_selector;
+	u16 host_ss_selector;
+	u16 host_ds_selector;
+	u16 host_fs_selector;
+	u16 host_gs_selector;
+	u16 host_tr_selector;
+};
+
+/*
+ * VMCS12_REVISION is an arbitrary id that should be changed if the content or
+ * layout of struct vmcs12 is changed. MSR_IA32_VMX_BASIC returns this id, and
+ * VMPTRLD verifies that the VMCS region that L1 is loading contains this id.
+ */
+#define VMCS12_REVISION 0x11e57ed0
+
+/*
+ * VMCS12_SIZE is the number of bytes L1 should allocate for the VMXON region
+ * and any VMCS region. Although only sizeof(struct vmcs12) are used by the
+ * current implementation, 4K are reserved to avoid future complications.
+ */
+#define VMCS12_SIZE 0x1000
+
+/* Used to remember the last vmcs02 used for some recently used vmcs12s */
+struct vmcs02_list {
+	struct list_head list;
+	gpa_t vmptr;
+	struct loaded_vmcs vmcs02;
+};
+
+/*
+ * The nested_vmx structure is part of vcpu_vmx, and holds information we need
+ * for correct emulation of VMX (i.e., nested VMX) on this vcpu.
+ */
+struct nested_vmx {
+	/* Has the level1 guest done vmxon? */
+	bool vmxon;
+
+	/* The guest-physical address of the current VMCS L1 keeps for L2 */
+	gpa_t current_vmptr;
+	/* The host-usable pointer to the above */
+	struct page *current_vmcs12_page;
+	struct vmcs12 *current_vmcs12;
+
+	/* vmcs02_list cache of VMCSs recently used to run L2 guests */
+	struct list_head vmcs02_pool;
+	int vmcs02_num;
+	u64 vmcs01_tsc_offset;
+	/* L2 must run next, and mustn't decide to exit to L1. */
+	bool nested_run_pending;
+	/*
+	 * Guest pages referred to in vmcs02 with host-physical pointers, so
+	 * we must keep them pinned while L2 runs.
+	 */
+	struct page *apic_access_page;
+};
+
 struct vcpu_vmx {
 	struct kvm_vcpu       vcpu;
-	struct list_head      local_vcpus_link;
 	unsigned long         host_rsp;
-	int                   launched;
 	u8                    fail;
 	u8                    cpl;
 	bool                  nmi_known_unmasked;
@@ -140,7 +368,14 @@ struct vcpu_vmx {
 	u64 		      msr_host_kernel_gs_base;
 	u64 		      msr_guest_kernel_gs_base;
 #endif
-	struct vmcs          *vmcs;
+	/*
+	 * loaded_vmcs points to the VMCS currently used in this vcpu. For a
+	 * non-nested (L1) guest, it always points to vmcs01. For a nested
+	 * guest (L2), it points to a different VMCS.
+	 */
+	struct loaded_vmcs    vmcs01;
+	struct loaded_vmcs   *loaded_vmcs;
+	bool                  __launched; /* temporary, used in vmx_vcpu_run */
 	struct msr_autoload {
 		unsigned nr;
 		struct vmx_msr_entry guest[NR_AUTOLOAD_MSRS];
@@ -176,6 +411,9 @@ struct vcpu_vmx {
 	u32 exit_reason;
 
 	bool rdtscp_enabled;
+
+	/* Support for a guest hypervisor (nested VMX) */
+	struct nested_vmx nested;
 };
 
 enum segment_cache_field {
@@ -192,6 +430,174 @@ static inline struct vcpu_vmx *to_vmx(struct kvm_vcpu *vcpu)
 	return container_of(vcpu, struct vcpu_vmx, vcpu);
 }
 
+#define VMCS12_OFFSET(x) offsetof(struct vmcs12, x)
+#define FIELD(number, name)	[number] = VMCS12_OFFSET(name)
+#define FIELD64(number, name)	[number] = VMCS12_OFFSET(name), \
+				[number##_HIGH] = VMCS12_OFFSET(name)+4
+
+static unsigned short vmcs_field_to_offset_table[] = {
+	FIELD(VIRTUAL_PROCESSOR_ID, virtual_processor_id),
+	FIELD(GUEST_ES_SELECTOR, guest_es_selector),
+	FIELD(GUEST_CS_SELECTOR, guest_cs_selector),
+	FIELD(GUEST_SS_SELECTOR, guest_ss_selector),
+	FIELD(GUEST_DS_SELECTOR, guest_ds_selector),
+	FIELD(GUEST_FS_SELECTOR, guest_fs_selector),
+	FIELD(GUEST_GS_SELECTOR, guest_gs_selector),
+	FIELD(GUEST_LDTR_SELECTOR, guest_ldtr_selector),
+	FIELD(GUEST_TR_SELECTOR, guest_tr_selector),
+	FIELD(HOST_ES_SELECTOR, host_es_selector),
+	FIELD(HOST_CS_SELECTOR, host_cs_selector),
+	FIELD(HOST_SS_SELECTOR, host_ss_selector),
+	FIELD(HOST_DS_SELECTOR, host_ds_selector),
+	FIELD(HOST_FS_SELECTOR, host_fs_selector),
+	FIELD(HOST_GS_SELECTOR, host_gs_selector),
+	FIELD(HOST_TR_SELECTOR, host_tr_selector),
+	FIELD64(IO_BITMAP_A, io_bitmap_a),
+	FIELD64(IO_BITMAP_B, io_bitmap_b),
+	FIELD64(MSR_BITMAP, msr_bitmap),
+	FIELD64(VM_EXIT_MSR_STORE_ADDR, vm_exit_msr_store_addr),
+	FIELD64(VM_EXIT_MSR_LOAD_ADDR, vm_exit_msr_load_addr),
+	FIELD64(VM_ENTRY_MSR_LOAD_ADDR, vm_entry_msr_load_addr),
+	FIELD64(TSC_OFFSET, tsc_offset),
+	FIELD64(VIRTUAL_APIC_PAGE_ADDR, virtual_apic_page_addr),
+	FIELD64(APIC_ACCESS_ADDR, apic_access_addr),
+	FIELD64(EPT_POINTER, ept_pointer),
+	FIELD64(GUEST_PHYSICAL_ADDRESS, guest_physical_address),
+	FIELD64(VMCS_LINK_POINTER, vmcs_link_pointer),
+	FIELD64(GUEST_IA32_DEBUGCTL, guest_ia32_debugctl),
+	FIELD64(GUEST_IA32_PAT, guest_ia32_pat),
+	FIELD64(GUEST_IA32_EFER, guest_ia32_efer),
+	FIELD64(GUEST_IA32_PERF_GLOBAL_CTRL, guest_ia32_perf_global_ctrl),
+	FIELD64(GUEST_PDPTR0, guest_pdptr0),
+	FIELD64(GUEST_PDPTR1, guest_pdptr1),
+	FIELD64(GUEST_PDPTR2, guest_pdptr2),
+	FIELD64(GUEST_PDPTR3, guest_pdptr3),
+	FIELD64(HOST_IA32_PAT, host_ia32_pat),
+	FIELD64(HOST_IA32_EFER, host_ia32_efer),
+	FIELD64(HOST_IA32_PERF_GLOBAL_CTRL, host_ia32_perf_global_ctrl),
+	FIELD(PIN_BASED_VM_EXEC_CONTROL, pin_based_vm_exec_control),
+	FIELD(CPU_BASED_VM_EXEC_CONTROL, cpu_based_vm_exec_control),
+	FIELD(EXCEPTION_BITMAP, exception_bitmap),
+	FIELD(PAGE_FAULT_ERROR_CODE_MASK, page_fault_error_code_mask),
+	FIELD(PAGE_FAULT_ERROR_CODE_MATCH, page_fault_error_code_match),
+	FIELD(CR3_TARGET_COUNT, cr3_target_count),
+	FIELD(VM_EXIT_CONTROLS, vm_exit_controls),
+	FIELD(VM_EXIT_MSR_STORE_COUNT, vm_exit_msr_store_count),
+	FIELD(VM_EXIT_MSR_LOAD_COUNT, vm_exit_msr_load_count),
+	FIELD(VM_ENTRY_CONTROLS, vm_entry_controls),
+	FIELD(VM_ENTRY_MSR_LOAD_COUNT, vm_entry_msr_load_count),
+	FIELD(VM_ENTRY_INTR_INFO_FIELD, vm_entry_intr_info_field),
+	FIELD(VM_ENTRY_EXCEPTION_ERROR_CODE, vm_entry_exception_error_code),
+	FIELD(VM_ENTRY_INSTRUCTION_LEN, vm_entry_instruction_len),
+	FIELD(TPR_THRESHOLD, tpr_threshold),
+	FIELD(SECONDARY_VM_EXEC_CONTROL, secondary_vm_exec_control),
+	FIELD(VM_INSTRUCTION_ERROR, vm_instruction_error),
+	FIELD(VM_EXIT_REASON, vm_exit_reason),
+	FIELD(VM_EXIT_INTR_INFO, vm_exit_intr_info),
+	FIELD(VM_EXIT_INTR_ERROR_CODE, vm_exit_intr_error_code),
+	FIELD(IDT_VECTORING_INFO_FIELD, idt_vectoring_info_field),
+	FIELD(IDT_VECTORING_ERROR_CODE, idt_vectoring_error_code),
+	FIELD(VM_EXIT_INSTRUCTION_LEN, vm_exit_instruction_len),
+	FIELD(VMX_INSTRUCTION_INFO, vmx_instruction_info),
+	FIELD(GUEST_ES_LIMIT, guest_es_limit),
+	FIELD(GUEST_CS_LIMIT, guest_cs_limit),
+	FIELD(GUEST_SS_LIMIT, guest_ss_limit),
+	FIELD(GUEST_DS_LIMIT, guest_ds_limit),
+	FIELD(GUEST_FS_LIMIT, guest_fs_limit),
+	FIELD(GUEST_GS_LIMIT, guest_gs_limit),
+	FIELD(GUEST_LDTR_LIMIT, guest_ldtr_limit),
+	FIELD(GUEST_TR_LIMIT, guest_tr_limit),
+	FIELD(GUEST_GDTR_LIMIT, guest_gdtr_limit),
+	FIELD(GUEST_IDTR_LIMIT, guest_idtr_limit),
+	FIELD(GUEST_ES_AR_BYTES, guest_es_ar_bytes),
+	FIELD(GUEST_CS_AR_BYTES, guest_cs_ar_bytes),
+	FIELD(GUEST_SS_AR_BYTES, guest_ss_ar_bytes),
+	FIELD(GUEST_DS_AR_BYTES, guest_ds_ar_bytes),
+	FIELD(GUEST_FS_AR_BYTES, guest_fs_ar_bytes),
+	FIELD(GUEST_GS_AR_BYTES, guest_gs_ar_bytes),
+	FIELD(GUEST_LDTR_AR_BYTES, guest_ldtr_ar_bytes),
+	FIELD(GUEST_TR_AR_BYTES, guest_tr_ar_bytes),
+	FIELD(GUEST_INTERRUPTIBILITY_INFO, guest_interruptibility_info),
+	FIELD(GUEST_ACTIVITY_STATE, guest_activity_state),
+	FIELD(GUEST_SYSENTER_CS, guest_sysenter_cs),
+	FIELD(HOST_IA32_SYSENTER_CS, host_ia32_sysenter_cs),
+	FIELD(CR0_GUEST_HOST_MASK, cr0_guest_host_mask),
+	FIELD(CR4_GUEST_HOST_MASK, cr4_guest_host_mask),
+	FIELD(CR0_READ_SHADOW, cr0_read_shadow),
+	FIELD(CR4_READ_SHADOW, cr4_read_shadow),
+	FIELD(CR3_TARGET_VALUE0, cr3_target_value0),
+	FIELD(CR3_TARGET_VALUE1, cr3_target_value1),
+	FIELD(CR3_TARGET_VALUE2, cr3_target_value2),
+	FIELD(CR3_TARGET_VALUE3, cr3_target_value3),
+	FIELD(EXIT_QUALIFICATION, exit_qualification),
+	FIELD(GUEST_LINEAR_ADDRESS, guest_linear_address),
+	FIELD(GUEST_CR0, guest_cr0),
+	FIELD(GUEST_CR3, guest_cr3),
+	FIELD(GUEST_CR4, guest_cr4),
+	FIELD(GUEST_ES_BASE, guest_es_base),
+	FIELD(GUEST_CS_BASE, guest_cs_base),
+	FIELD(GUEST_SS_BASE, guest_ss_base),
+	FIELD(GUEST_DS_BASE, guest_ds_base),
+	FIELD(GUEST_FS_BASE, guest_fs_base),
+	FIELD(GUEST_GS_BASE, guest_gs_base),
+	FIELD(GUEST_LDTR_BASE, guest_ldtr_base),
+	FIELD(GUEST_TR_BASE, guest_tr_base),
+	FIELD(GUEST_GDTR_BASE, guest_gdtr_base),
+	FIELD(GUEST_IDTR_BASE, guest_idtr_base),
+	FIELD(GUEST_DR7, guest_dr7),
+	FIELD(GUEST_RSP, guest_rsp),
+	FIELD(GUEST_RIP, guest_rip),
+	FIELD(GUEST_RFLAGS, guest_rflags),
+	FIELD(GUEST_PENDING_DBG_EXCEPTIONS, guest_pending_dbg_exceptions),
+	FIELD(GUEST_SYSENTER_ESP, guest_sysenter_esp),
+	FIELD(GUEST_SYSENTER_EIP, guest_sysenter_eip),
+	FIELD(HOST_CR0, host_cr0),
+	FIELD(HOST_CR3, host_cr3),
+	FIELD(HOST_CR4, host_cr4),
+	FIELD(HOST_FS_BASE, host_fs_base),
+	FIELD(HOST_GS_BASE, host_gs_base),
+	FIELD(HOST_TR_BASE, host_tr_base),
+	FIELD(HOST_GDTR_BASE, host_gdtr_base),
+	FIELD(HOST_IDTR_BASE, host_idtr_base),
+	FIELD(HOST_IA32_SYSENTER_ESP, host_ia32_sysenter_esp),
+	FIELD(HOST_IA32_SYSENTER_EIP, host_ia32_sysenter_eip),
+	FIELD(HOST_RSP, host_rsp),
+	FIELD(HOST_RIP, host_rip),
+};
+static const int max_vmcs_field = ARRAY_SIZE(vmcs_field_to_offset_table);
+
+static inline short vmcs_field_to_offset(unsigned long field)
+{
+	if (field >= max_vmcs_field || vmcs_field_to_offset_table[field] == 0)
+		return -1;
+	return vmcs_field_to_offset_table[field];
+}
+
+static inline struct vmcs12 *get_vmcs12(struct kvm_vcpu *vcpu)
+{
+	return to_vmx(vcpu)->nested.current_vmcs12;
+}
+
+static struct page *nested_get_page(struct kvm_vcpu *vcpu, gpa_t addr)
+{
+	struct page *page = gfn_to_page(vcpu->kvm, addr >> PAGE_SHIFT);
+	if (is_error_page(page)) {
+		kvm_release_page_clean(page);
+		return NULL;
+	}
+	return page;
+}
+
+static void nested_release_page(struct page *page)
+{
+	kvm_release_page_dirty(page);
+}
+
+static void nested_release_page_clean(struct page *page)
+{
+	kvm_release_page_clean(page);
+}
+
 static u64 construct_eptp(unsigned long root_hpa);
 static void kvm_cpu_vmxon(u64 addr);
 static void kvm_cpu_vmxoff(void);
@@ -200,7 +606,11 @@ static int vmx_set_tss_addr(struct kvm *kvm, unsigned int addr);
 
 static DEFINE_PER_CPU(struct vmcs *, vmxarea);
 static DEFINE_PER_CPU(struct vmcs *, current_vmcs);
-static DEFINE_PER_CPU(struct list_head, vcpus_on_cpu);
+/*
+ * We maintain a per-CPU linked-list of VMCS loaded on that CPU. This is needed
+ * when a CPU is brought down, and we need to VMCLEAR all VMCSs loaded on it.
+ */
+static DEFINE_PER_CPU(struct list_head, loaded_vmcss_on_cpu);
 static DEFINE_PER_CPU(struct desc_ptr, host_gdt);
 
 static unsigned long *vmx_io_bitmap_a;
@@ -442,6 +852,35 @@ static inline bool report_flexpriority(void)
 	return flexpriority_enabled;
 }
 
+static inline bool nested_cpu_has(struct vmcs12 *vmcs12, u32 bit)
+{
+	return vmcs12->cpu_based_vm_exec_control & bit;
+}
+
+static inline bool nested_cpu_has2(struct vmcs12 *vmcs12, u32 bit)
+{
+	return (vmcs12->cpu_based_vm_exec_control &
+			CPU_BASED_ACTIVATE_SECONDARY_CONTROLS) &&
+		(vmcs12->secondary_vm_exec_control & bit);
+}
+
+static inline bool nested_cpu_has_virtual_nmis(struct vmcs12 *vmcs12,
+	struct kvm_vcpu *vcpu)
+{
+	return vmcs12->pin_based_vm_exec_control & PIN_BASED_VIRTUAL_NMIS;
+}
+
+static inline bool is_exception(u32 intr_info)
+{
+	return (intr_info & (INTR_INFO_INTR_TYPE_MASK | INTR_INFO_VALID_MASK))
+		== (INTR_TYPE_HARD_EXCEPTION | INTR_INFO_VALID_MASK);
+}
+
+static void nested_vmx_vmexit(struct kvm_vcpu *vcpu);
+static void nested_vmx_entry_failure(struct kvm_vcpu *vcpu,
+			struct vmcs12 *vmcs12,
+			u32 reason, unsigned long qualification);
+
 static int __find_msr_index(struct vcpu_vmx *vmx, u32 msr)
 {
 	int i;
@@ -501,6 +940,13 @@ static void vmcs_clear(struct vmcs *vmcs)
 		       vmcs, phys_addr);
 }
 
+static inline void loaded_vmcs_init(struct loaded_vmcs *loaded_vmcs)
+{
+	vmcs_clear(loaded_vmcs->vmcs);
+	loaded_vmcs->cpu = -1;
+	loaded_vmcs->launched = 0;
+}
+
 static void vmcs_load(struct vmcs *vmcs)
 {
 	u64 phys_addr = __pa(vmcs);
@@ -510,29 +956,28 @@ static void vmcs_load(struct vmcs *vmcs)
 			: "=qm"(error) : "a"(&phys_addr), "m"(phys_addr)
 			: "cc", "memory");
 	if (error)
-		printk(KERN_ERR "kvm: vmptrld %p/%llx fail\n",
+		printk(KERN_ERR "kvm: vmptrld %p/%llx failed\n",
 		       vmcs, phys_addr);
 }
 
-static void __vcpu_clear(void *arg)
+static void __loaded_vmcs_clear(void *arg)
 {
-	struct vcpu_vmx *vmx = arg;
+	struct loaded_vmcs *loaded_vmcs = arg;
 	int cpu = raw_smp_processor_id();
 
-	if (vmx->vcpu.cpu == cpu)
-		vmcs_clear(vmx->vmcs);
-	if (per_cpu(current_vmcs, cpu) == vmx->vmcs)
+	if (loaded_vmcs->cpu != cpu)
+		return; /* vcpu migration can race with cpu offline */
+	if (per_cpu(current_vmcs, cpu) == loaded_vmcs->vmcs)
 		per_cpu(current_vmcs, cpu) = NULL;
-	list_del(&vmx->local_vcpus_link);
-	vmx->vcpu.cpu = -1;
-	vmx->launched = 0;
+	list_del(&loaded_vmcs->loaded_vmcss_on_cpu_link);
+	loaded_vmcs_init(loaded_vmcs);
 }
 
-static void vcpu_clear(struct vcpu_vmx *vmx)
+static void loaded_vmcs_clear(struct loaded_vmcs *loaded_vmcs)
 {
-	if (vmx->vcpu.cpu == -1)
-		return;
-	smp_call_function_single(vmx->vcpu.cpu, __vcpu_clear, vmx, 1);
+	if (loaded_vmcs->cpu != -1)
+		smp_call_function_single(
+			loaded_vmcs->cpu, __loaded_vmcs_clear, loaded_vmcs, 1);
 }
 
 static inline void vpid_sync_vcpu_single(struct vcpu_vmx *vmx)
@@ -585,26 +1030,26 @@ static inline void ept_sync_individual_addr(u64 eptp, gpa_t gpa)
 	}
 }
 
-static unsigned long vmcs_readl(unsigned long field)
+static __always_inline unsigned long vmcs_readl(unsigned long field)
 {
-	unsigned long value = 0;
+	unsigned long value;
 
-	asm volatile (__ex(ASM_VMX_VMREAD_RDX_RAX)
-		      : "+a"(value) : "d"(field) : "cc");
+	asm volatile (__ex_clear(ASM_VMX_VMREAD_RDX_RAX, "%0")
+		      : "=a"(value) : "d"(field) : "cc");
 	return value;
 }
 
-static u16 vmcs_read16(unsigned long field)
+static __always_inline u16 vmcs_read16(unsigned long field)
 {
 	return vmcs_readl(field);
 }
 
-static u32 vmcs_read32(unsigned long field)
+static __always_inline u32 vmcs_read32(unsigned long field)
 {
 	return vmcs_readl(field);
 }
 
-static u64 vmcs_read64(unsigned long field)
+static __always_inline u64 vmcs_read64(unsigned long field)
 {
 #ifdef CONFIG_X86_64
 	return vmcs_readl(field);
@@ -731,6 +1176,15 @@ static void update_exception_bitmap(struct kvm_vcpu *vcpu)
 		eb &= ~(1u << PF_VECTOR); /* bypass_guest_pf = 0 */
 	if (vcpu->fpu_active)
 		eb &= ~(1u << NM_VECTOR);
+
+	/* When we are running a nested L2 guest and L1 specified for it a
+	 * certain exception bitmap, we must trap the same exceptions and pass
+	 * them to L1. When running L2, we will only handle the exceptions
+	 * specified above if L1 did not want them.
+	 */
+	if (is_guest_mode(vcpu))
+		eb |= get_vmcs12(vcpu)->exception_bitmap;
+
 	vmcs_write32(EXCEPTION_BITMAP, eb);
 }
 
@@ -971,22 +1425,22 @@ static void vmx_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
 
 	if (!vmm_exclusive)
 		kvm_cpu_vmxon(phys_addr);
-	else if (vcpu->cpu != cpu)
-		vcpu_clear(vmx);
+	else if (vmx->loaded_vmcs->cpu != cpu)
+		loaded_vmcs_clear(vmx->loaded_vmcs);
 
-	if (per_cpu(current_vmcs, cpu) != vmx->vmcs) {
-		per_cpu(current_vmcs, cpu) = vmx->vmcs;
-		vmcs_load(vmx->vmcs);
+	if (per_cpu(current_vmcs, cpu) != vmx->loaded_vmcs->vmcs) {
+		per_cpu(current_vmcs, cpu) = vmx->loaded_vmcs->vmcs;
+		vmcs_load(vmx->loaded_vmcs->vmcs);
 	}
 
-	if (vcpu->cpu != cpu) {
+	if (vmx->loaded_vmcs->cpu != cpu) {
 		struct desc_ptr *gdt = &__get_cpu_var(host_gdt);
 		unsigned long sysenter_esp;
 
 		kvm_make_request(KVM_REQ_TLB_FLUSH, vcpu);
 		local_irq_disable();
-		list_add(&vmx->local_vcpus_link,
-			 &per_cpu(vcpus_on_cpu, cpu));
+		list_add(&vmx->loaded_vmcs->loaded_vmcss_on_cpu_link,
+			 &per_cpu(loaded_vmcss_on_cpu, cpu));
 		local_irq_enable();
 
 		/*
@@ -998,6 +1452,7 @@ static void vmx_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
 
 		rdmsrl(MSR_IA32_SYSENTER_ESP, sysenter_esp);
 		vmcs_writel(HOST_IA32_SYSENTER_ESP, sysenter_esp); /* 22.2.3 */
+		vmx->loaded_vmcs->cpu = cpu;
 	}
 }
 
@@ -1005,7 +1460,8 @@ static void vmx_vcpu_put(struct kvm_vcpu *vcpu)
 {
 	__vmx_load_host_state(to_vmx(vcpu));
 	if (!vmm_exclusive) {
-		__vcpu_clear(to_vmx(vcpu));
+		__loaded_vmcs_clear(to_vmx(vcpu)->loaded_vmcs);
+		vcpu->cpu = -1;
 		kvm_cpu_vmxoff();
 	}
 }
@@ -1023,19 +1479,55 @@ static void vmx_fpu_activate(struct kvm_vcpu *vcpu)
 	vmcs_writel(GUEST_CR0, cr0);
 	update_exception_bitmap(vcpu);
 	vcpu->arch.cr0_guest_owned_bits = X86_CR0_TS;
+	if (is_guest_mode(vcpu))
+		vcpu->arch.cr0_guest_owned_bits &=
+			~get_vmcs12(vcpu)->cr0_guest_host_mask;
 	vmcs_writel(CR0_GUEST_HOST_MASK, ~vcpu->arch.cr0_guest_owned_bits);
 }
 
 static void vmx_decache_cr0_guest_bits(struct kvm_vcpu *vcpu);
 
+/*
+ * Return the cr0 value that a nested guest would read. This is a combination
+ * of the real cr0 used to run the guest (guest_cr0), and the bits shadowed by
+ * its hypervisor (cr0_read_shadow).
+ */
+static inline unsigned long nested_read_cr0(struct vmcs12 *fields)
+{
+	return (fields->guest_cr0 & ~fields->cr0_guest_host_mask) |
+		(fields->cr0_read_shadow & fields->cr0_guest_host_mask);
+}
+static inline unsigned long nested_read_cr4(struct vmcs12 *fields)
+{
+	return (fields->guest_cr4 & ~fields->cr4_guest_host_mask) |
+		(fields->cr4_read_shadow & fields->cr4_guest_host_mask);
+}
+
 static void vmx_fpu_deactivate(struct kvm_vcpu *vcpu)
 {
+	/* Note that there is no vcpu->fpu_active = 0 here. The caller must
+	 * set this *before* calling this function.
+	 */
 	vmx_decache_cr0_guest_bits(vcpu);
 	vmcs_set_bits(GUEST_CR0, X86_CR0_TS | X86_CR0_MP);
 	update_exception_bitmap(vcpu);
 	vcpu->arch.cr0_guest_owned_bits = 0;
 	vmcs_writel(CR0_GUEST_HOST_MASK, ~vcpu->arch.cr0_guest_owned_bits);
-	vmcs_writel(CR0_READ_SHADOW, vcpu->arch.cr0);
+	if (is_guest_mode(vcpu)) {
+		/*
+		 * L1's specified read shadow might not contain the TS bit,
+		 * so now that we turned on shadowing of this bit, we need to
+		 * set this bit of the shadow. Like in nested_vmx_run we need
+		 * nested_read_cr0(vmcs12), but vmcs12->guest_cr0 is not yet
+		 * up-to-date here because we just decached cr0.TS (and we'll
+		 * only update vmcs12->guest_cr0 on nested exit).
+		 */
+		struct vmcs12 *vmcs12 = get_vmcs12(vcpu);
+		vmcs12->guest_cr0 = (vmcs12->guest_cr0 & ~X86_CR0_TS) |
+			(vcpu->arch.cr0 & X86_CR0_TS);
+		vmcs_writel(CR0_READ_SHADOW, nested_read_cr0(vmcs12));
+	} else
+		vmcs_writel(CR0_READ_SHADOW, vcpu->arch.cr0);
 }
 
 static unsigned long vmx_get_rflags(struct kvm_vcpu *vcpu)
@@ -1119,6 +1611,25 @@ static void vmx_clear_hlt(struct kvm_vcpu *vcpu)
 		vmcs_write32(GUEST_ACTIVITY_STATE, GUEST_ACTIVITY_ACTIVE);
 }
 
+/*
+ * KVM wants to inject page-faults which it got to the guest. This function
+ * checks whether in a nested guest, we need to inject them to L1 or L2.
+ * This function assumes it is called with the exit reason in vmcs02 being
+ * a #PF exception (this is the only case in which KVM injects a #PF when L2
+ * is running).
+ */
+static int nested_pf_handled(struct kvm_vcpu *vcpu)
+{
+	struct vmcs12 *vmcs12 = get_vmcs12(vcpu);
+
+	/* TODO: also check PFEC_MATCH/MASK, not just EB.PF. */
+	if (!(vmcs12->exception_bitmap & PF_VECTOR))
+		return 0;
+
+	nested_vmx_vmexit(vcpu);
+	return 1;
+}
+
 static void vmx_queue_exception(struct kvm_vcpu *vcpu, unsigned nr,
 				bool has_error_code, u32 error_code,
 				bool reinject)
@@ -1126,6 +1637,10 @@ static void vmx_queue_exception(struct kvm_vcpu *vcpu, unsigned nr,
 	struct vcpu_vmx *vmx = to_vmx(vcpu);
 	u32 intr_info = nr | INTR_INFO_VALID_MASK;
 
+	if (nr == PF_VECTOR && is_guest_mode(vcpu) &&
+		nested_pf_handled(vcpu))
+		return;
+
 	if (has_error_code) {
 		vmcs_write32(VM_ENTRY_EXCEPTION_ERROR_CODE, error_code);
 		intr_info |= INTR_INFO_DELIVER_CODE_MASK;
@@ -1248,12 +1763,24 @@ static void vmx_set_tsc_khz(struct kvm_vcpu *vcpu, u32 user_tsc_khz)
 static void vmx_write_tsc_offset(struct kvm_vcpu *vcpu, u64 offset)
 {
 	vmcs_write64(TSC_OFFSET, offset);
+	if (is_guest_mode(vcpu))
+		/*
+		 * We're here if L1 chose not to trap the TSC MSR. Since
+		 * prepare_vmcs12() does not copy tsc_offset, we need to also
+		 * set the vmcs12 field here.
+		 */
+		get_vmcs12(vcpu)->tsc_offset = offset -
+			to_vmx(vcpu)->nested.vmcs01_tsc_offset;
 }
 
 static void vmx_adjust_tsc_offset(struct kvm_vcpu *vcpu, s64 adjustment)
 {
 	u64 offset = vmcs_read64(TSC_OFFSET);
 	vmcs_write64(TSC_OFFSET, offset + adjustment);
+	if (is_guest_mode(vcpu)) {
+		/* Even when running L2, the adjustment needs to apply to L1 */
+		to_vmx(vcpu)->nested.vmcs01_tsc_offset += adjustment;
+	}
 }
 
 static u64 vmx_compute_tsc_offset(struct kvm_vcpu *vcpu, u64 target_tsc)
@@ -1261,6 +1788,236 @@ static u64 vmx_compute_tsc_offset(struct kvm_vcpu *vcpu, u64 target_tsc)
 	return target_tsc - native_read_tsc();
 }
 
+static bool guest_cpuid_has_vmx(struct kvm_vcpu *vcpu)
+{
+	struct kvm_cpuid_entry2 *best = kvm_find_cpuid_entry(vcpu, 1, 0);
+	return best && (best->ecx & (1 << (X86_FEATURE_VMX & 31)));
+}
+
+/*
+ * nested_vmx_allowed() checks whether a guest should be allowed to use VMX
+ * instructions and MSRs (i.e., nested VMX). Nested VMX is disabled for
+ * all guests if the "nested" module option is off, and can also be disabled
+ * for a single guest by disabling its VMX cpuid bit.
+ */
+static inline bool nested_vmx_allowed(struct kvm_vcpu *vcpu)
+{
+	return nested && guest_cpuid_has_vmx(vcpu);
+}
+
+/*
+ * nested_vmx_setup_ctls_msrs() sets up variables containing the values to be
+ * returned for the various VMX controls MSRs when nested VMX is enabled.
+ * The same values should also be used to verify that vmcs12 control fields are
+ * valid during nested entry from L1 to L2.
+ * Each of these control msrs has a low and high 32-bit half: A low bit is on
+ * if the corresponding bit in the (32-bit) control field *must* be on, and a
+ * bit in the high half is on if the corresponding bit in the control field
+ * may be on. See also vmx_control_verify().
+ * TODO: allow these variables to be modified (downgraded) by module options
+ * or other means.
+ */
+static u32 nested_vmx_procbased_ctls_low, nested_vmx_procbased_ctls_high;
+static u32 nested_vmx_secondary_ctls_low, nested_vmx_secondary_ctls_high;
+static u32 nested_vmx_pinbased_ctls_low, nested_vmx_pinbased_ctls_high;
+static u32 nested_vmx_exit_ctls_low, nested_vmx_exit_ctls_high;
+static u32 nested_vmx_entry_ctls_low, nested_vmx_entry_ctls_high;
+static __init void nested_vmx_setup_ctls_msrs(void)
+{
+	/*
+	 * Note that as a general rule, the high half of the MSRs (bits in
+	 * the control fields which may be 1) should be initialized by the
+	 * intersection of the underlying hardware's MSR (i.e., features which
+	 * can be supported) and the list of features we want to expose -
+	 * because they are known to be properly supported in our code.
+	 * Also, usually, the low half of the MSRs (bits which must be 1) can
+	 * be set to 0, meaning that L1 may turn off any of these bits. The
+	 * reason is that if one of these bits is necessary, it will appear
+	 * in vmcs01 and prepare_vmcs02, when it bitwise-or's the control
+	 * fields of vmcs01 and vmcs02, will turn these bits off - and
+	 * nested_vmx_exit_handled() will not pass related exits to L1.
+	 * These rules have exceptions below.
+	 */
+
+	/* pin-based controls */
+	/*
+	 * According to the Intel spec, if bit 55 of VMX_BASIC is off (as it is
+	 * in our case), bits 1, 2 and 4 (i.e., 0x16) must be 1 in this MSR.
+	 */
+	nested_vmx_pinbased_ctls_low = 0x16 ;
+	nested_vmx_pinbased_ctls_high = 0x16 |
+		PIN_BASED_EXT_INTR_MASK | PIN_BASED_NMI_EXITING |
+		PIN_BASED_VIRTUAL_NMIS;
+
+	/* exit controls */
+	nested_vmx_exit_ctls_low = 0;
+	/* Note that guest use of VM_EXIT_ACK_INTR_ON_EXIT is not supported. */
+#ifdef CONFIG_X86_64
+	nested_vmx_exit_ctls_high = VM_EXIT_HOST_ADDR_SPACE_SIZE;
+#else
+	nested_vmx_exit_ctls_high = 0;
+#endif
+
+	/* entry controls */
+	rdmsr(MSR_IA32_VMX_ENTRY_CTLS,
+		nested_vmx_entry_ctls_low, nested_vmx_entry_ctls_high);
+	nested_vmx_entry_ctls_low = 0;
+	nested_vmx_entry_ctls_high &=
+		VM_ENTRY_LOAD_IA32_PAT | VM_ENTRY_IA32E_MODE;
+
+	/* cpu-based controls */
+	rdmsr(MSR_IA32_VMX_PROCBASED_CTLS,
+		nested_vmx_procbased_ctls_low, nested_vmx_procbased_ctls_high);
+	nested_vmx_procbased_ctls_low = 0;
+	nested_vmx_procbased_ctls_high &=
+		CPU_BASED_VIRTUAL_INTR_PENDING | CPU_BASED_USE_TSC_OFFSETING |
+		CPU_BASED_HLT_EXITING | CPU_BASED_INVLPG_EXITING |
+		CPU_BASED_MWAIT_EXITING | CPU_BASED_CR3_LOAD_EXITING |
+		CPU_BASED_CR3_STORE_EXITING |
+#ifdef CONFIG_X86_64
+		CPU_BASED_CR8_LOAD_EXITING | CPU_BASED_CR8_STORE_EXITING |
+#endif
+		CPU_BASED_MOV_DR_EXITING | CPU_BASED_UNCOND_IO_EXITING |
+		CPU_BASED_USE_IO_BITMAPS | CPU_BASED_MONITOR_EXITING |
+		CPU_BASED_ACTIVATE_SECONDARY_CONTROLS;
+	/*
+	 * We can allow some features even when not supported by the
+	 * hardware. For example, L1 can specify an MSR bitmap - and we
+	 * can use it to avoid exits to L1 - even when L0 runs L2
+	 * without MSR bitmaps.
+	 */
+	nested_vmx_procbased_ctls_high |= CPU_BASED_USE_MSR_BITMAPS;
+
+	/* secondary cpu-based controls */
+	rdmsr(MSR_IA32_VMX_PROCBASED_CTLS2,
+		nested_vmx_secondary_ctls_low, nested_vmx_secondary_ctls_high);
+	nested_vmx_secondary_ctls_low = 0;
+	nested_vmx_secondary_ctls_high &=
+		SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES;
+}
+
+static inline bool vmx_control_verify(u32 control, u32 low, u32 high)
+{
+	/*
+	 * Bits 0 in high must be 0, and bits 1 in low must be 1.
+	 */
+	return ((control & high) | low) == control;
+}
+
+static inline u64 vmx_control_msr(u32 low, u32 high)
+{
+	return low | ((u64)high << 32);
+}
+
+/*
+ * If we allow our guest to use VMX instructions (i.e., nested VMX), we should
+ * also let it use VMX-specific MSRs.
+ * vmx_get_vmx_msr() and vmx_set_vmx_msr() return 1 when we handled a
+ * VMX-specific MSR, or 0 when we haven't (and the caller should handle it
+ * like all other MSRs).
+ */
+static int vmx_get_vmx_msr(struct kvm_vcpu *vcpu, u32 msr_index, u64 *pdata)
+{
+	if (!nested_vmx_allowed(vcpu) && msr_index >= MSR_IA32_VMX_BASIC &&
+		     msr_index <= MSR_IA32_VMX_TRUE_ENTRY_CTLS) {
+		/*
+		 * According to the spec, processors which do not support VMX
+		 * should throw a #GP(0) when VMX capability MSRs are read.
+		 */
+		kvm_queue_exception_e(vcpu, GP_VECTOR, 0);
+		return 1;
+	}
+
+	switch (msr_index) {
+	case MSR_IA32_FEATURE_CONTROL:
+		*pdata = 0;
+		break;
+	case MSR_IA32_VMX_BASIC:
+		/*
+		 * This MSR reports some information about VMX support. We
+		 * should return information about the VMX we emulate for the
+		 * guest, and the VMCS structure we give it - not about the
+		 * VMX support of the underlying hardware.
+		 */
+		*pdata = VMCS12_REVISION |
+			   ((u64)VMCS12_SIZE << VMX_BASIC_VMCS_SIZE_SHIFT) |
+			   (VMX_BASIC_MEM_TYPE_WB << VMX_BASIC_MEM_TYPE_SHIFT);
+		break;
+	case MSR_IA32_VMX_TRUE_PINBASED_CTLS:
+	case MSR_IA32_VMX_PINBASED_CTLS:
+		*pdata = vmx_control_msr(nested_vmx_pinbased_ctls_low,
+					nested_vmx_pinbased_ctls_high);
+		break;
+	case MSR_IA32_VMX_TRUE_PROCBASED_CTLS:
+	case MSR_IA32_VMX_PROCBASED_CTLS:
+		*pdata = vmx_control_msr(nested_vmx_procbased_ctls_low,
+					nested_vmx_procbased_ctls_high);
+		break;
+	case MSR_IA32_VMX_TRUE_EXIT_CTLS:
+	case MSR_IA32_VMX_EXIT_CTLS:
+		*pdata = vmx_control_msr(nested_vmx_exit_ctls_low,
+					nested_vmx_exit_ctls_high);
+		break;
+	case MSR_IA32_VMX_TRUE_ENTRY_CTLS:
+	case MSR_IA32_VMX_ENTRY_CTLS:
+		*pdata = vmx_control_msr(nested_vmx_entry_ctls_low,
+					nested_vmx_entry_ctls_high);
+		break;
+	case MSR_IA32_VMX_MISC:
+		*pdata = 0;
+		break;
+	/*
+	 * These MSRs specify bits which the guest must keep fixed (on or off)
+	 * while L1 is in VMXON mode (in L1's root mode, or running an L2).
+	 * We picked the standard core2 setting.
+	 */
+#define VMXON_CR0_ALWAYSON	(X86_CR0_PE | X86_CR0_PG | X86_CR0_NE)
+#define VMXON_CR4_ALWAYSON	X86_CR4_VMXE
+	case MSR_IA32_VMX_CR0_FIXED0:
+		*pdata = VMXON_CR0_ALWAYSON;
+		break;
+	case MSR_IA32_VMX_CR0_FIXED1:
+		*pdata = -1ULL;
+		break;
+	case MSR_IA32_VMX_CR4_FIXED0:
+		*pdata = VMXON_CR4_ALWAYSON;
+		break;
+	case MSR_IA32_VMX_CR4_FIXED1:
+		*pdata = -1ULL;
+		break;
+	case MSR_IA32_VMX_VMCS_ENUM:
+		*pdata = 0x1f;
+		break;
+	case MSR_IA32_VMX_PROCBASED_CTLS2:
+		*pdata = vmx_control_msr(nested_vmx_secondary_ctls_low,
+					nested_vmx_secondary_ctls_high);
+		break;
+	case MSR_IA32_VMX_EPT_VPID_CAP:
+		/* Currently, no nested ept or nested vpid */
+		*pdata = 0;
+		break;
+	default:
+		return 0;
+	}
+
+	return 1;
+}
+
+static int vmx_set_vmx_msr(struct kvm_vcpu *vcpu, u32 msr_index, u64 data)
+{
+	if (!nested_vmx_allowed(vcpu))
+		return 0;
+
+	if (msr_index == MSR_IA32_FEATURE_CONTROL)
+		/* TODO: the right thing. */
+		return 1;
+	/*
+	 * No need to treat VMX capability MSRs specially: If we don't handle
+	 * them, handle_wrmsr will #GP(0), which is correct (they are readonly)
+	 */
+	return 0;
+}
+
 /*
  * Reads an msr value (of 'msr_index') into 'pdata'.
  * Returns 0 on success, non-0 otherwise.
@@ -1309,6 +2066,8 @@ static int vmx_get_msr(struct kvm_vcpu *vcpu, u32 msr_index, u64 *pdata)
 		/* Otherwise falls through */
 	default:
 		vmx_load_host_state(to_vmx(vcpu));
+		if (vmx_get_vmx_msr(vcpu, msr_index, pdata))
+			return 0;
 		msr = find_msr_entry(to_vmx(vcpu), msr_index);
 		if (msr) {
 			vmx_load_host_state(to_vmx(vcpu));
@@ -1380,6 +2139,8 @@ static int vmx_set_msr(struct kvm_vcpu *vcpu, u32 msr_index, u64 data)
 			return 1;
 		/* Otherwise falls through */
 	default:
+		if (vmx_set_vmx_msr(vcpu, msr_index, data))
+			break;
 		msr = find_msr_entry(vmx, msr_index);
 		if (msr) {
 			vmx_load_host_state(vmx);
@@ -1469,7 +2230,7 @@ static int hardware_enable(void *garbage)
 	if (read_cr4() & X86_CR4_VMXE)
 		return -EBUSY;
 
-	INIT_LIST_HEAD(&per_cpu(vcpus_on_cpu, cpu));
+	INIT_LIST_HEAD(&per_cpu(loaded_vmcss_on_cpu, cpu));
 	rdmsrl(MSR_IA32_FEATURE_CONTROL, old);
 
 	test_bits = FEATURE_CONTROL_LOCKED;
@@ -1493,14 +2254,14 @@ static int hardware_enable(void *garbage)
 	return 0;
 }
 
-static void vmclear_local_vcpus(void)
+static void vmclear_local_loaded_vmcss(void)
 {
 	int cpu = raw_smp_processor_id();
-	struct vcpu_vmx *vmx, *n;
+	struct loaded_vmcs *v, *n;
 
-	list_for_each_entry_safe(vmx, n, &per_cpu(vcpus_on_cpu, cpu),
-				 local_vcpus_link)
-		__vcpu_clear(vmx);
+	list_for_each_entry_safe(v, n, &per_cpu(loaded_vmcss_on_cpu, cpu),
+				 loaded_vmcss_on_cpu_link)
+		__loaded_vmcs_clear(v);
 }
 
 
@@ -1515,7 +2276,7 @@ static void kvm_cpu_vmxoff(void)
 static void hardware_disable(void *garbage)
 {
 	if (vmm_exclusive) {
-		vmclear_local_vcpus();
+		vmclear_local_loaded_vmcss();
 		kvm_cpu_vmxoff();
 	}
 	write_cr4(read_cr4() & ~X86_CR4_VMXE);
@@ -1696,6 +2457,18 @@ static void free_vmcs(struct vmcs *vmcs)
 	free_pages((unsigned long)vmcs, vmcs_config.order);
 }
 
+/*
+ * Free a VMCS, but before that VMCLEAR it on the CPU where it was last loaded
+ */
+static void free_loaded_vmcs(struct loaded_vmcs *loaded_vmcs)
+{
+	if (!loaded_vmcs->vmcs)
+		return;
+	loaded_vmcs_clear(loaded_vmcs);
+	free_vmcs(loaded_vmcs->vmcs);
+	loaded_vmcs->vmcs = NULL;
+}
+
 static void free_kvm_area(void)
 {
 	int cpu;
@@ -1756,6 +2529,9 @@ static __init int hardware_setup(void)
 	if (!cpu_has_vmx_ple())
 		ple_gap = 0;
 
+	if (nested)
+		nested_vmx_setup_ctls_msrs();
+
 	return alloc_kvm_area();
 }
 
@@ -2041,7 +2817,7 @@ static void ept_save_pdptrs(struct kvm_vcpu *vcpu)
 		  (unsigned long *)&vcpu->arch.regs_dirty);
 }
 
-static void vmx_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4);
+static int vmx_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4);
 
 static void ept_update_paging_mode_cr0(unsigned long *hw_cr0,
 					unsigned long cr0,
@@ -2139,11 +2915,23 @@ static void vmx_set_cr3(struct kvm_vcpu *vcpu, unsigned long cr3)
 	vmcs_writel(GUEST_CR3, guest_cr3);
 }
 
-static void vmx_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4)
+static int vmx_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4)
 {
 	unsigned long hw_cr4 = cr4 | (to_vmx(vcpu)->rmode.vm86_active ?
 		    KVM_RMODE_VM_CR4_ALWAYS_ON : KVM_PMODE_VM_CR4_ALWAYS_ON);
 
+	if (cr4 & X86_CR4_VMXE) {
+		/*
+		 * To use VMXON (and later other VMX instructions), a guest
+		 * must first be able to turn on cr4.VMXE (see handle_vmon()).
+		 * So basically the check on whether to allow nested VMX
+		 * is here.
+		 */
+		if (!nested_vmx_allowed(vcpu))
+			return 1;
+	} else if (to_vmx(vcpu)->nested.vmxon)
+		return 1;
+
 	vcpu->arch.cr4 = cr4;
 	if (enable_ept) {
 		if (!is_paging(vcpu)) {
@@ -2156,6 +2944,7 @@ static void vmx_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4)
 
 	vmcs_writel(CR4_READ_SHADOW, cr4);
 	vmcs_writel(GUEST_CR4, hw_cr4);
+	return 0;
 }
 
 static void vmx_get_segment(struct kvm_vcpu *vcpu,
@@ -2721,18 +3510,110 @@ static void vmx_disable_intercept_for_msr(u32 msr, bool longmode_only)
 }
 
 /*
+ * Set up the vmcs's constant host-state fields, i.e., host-state fields that
+ * will not change in the lifetime of the guest.
+ * Note that host-state that does change is set elsewhere. E.g., host-state
+ * that is set differently for each CPU is set in vmx_vcpu_load(), not here.
+ */
+static void vmx_set_constant_host_state(void)
+{
+	u32 low32, high32;
+	unsigned long tmpl;
+	struct desc_ptr dt;
+
+	vmcs_writel(HOST_CR0, read_cr0() | X86_CR0_TS);  /* 22.2.3 */
+	vmcs_writel(HOST_CR4, read_cr4());  /* 22.2.3, 22.2.5 */
+	vmcs_writel(HOST_CR3, read_cr3());  /* 22.2.3  FIXME: shadow tables */
+
+	vmcs_write16(HOST_CS_SELECTOR, __KERNEL_CS);  /* 22.2.4 */
+	vmcs_write16(HOST_DS_SELECTOR, __KERNEL_DS);  /* 22.2.4 */
+	vmcs_write16(HOST_ES_SELECTOR, __KERNEL_DS);  /* 22.2.4 */
+	vmcs_write16(HOST_SS_SELECTOR, __KERNEL_DS);  /* 22.2.4 */
+	vmcs_write16(HOST_TR_SELECTOR, GDT_ENTRY_TSS*8);  /* 22.2.4 */
+
+	native_store_idt(&dt);
+	vmcs_writel(HOST_IDTR_BASE, dt.address);   /* 22.2.4 */
+
+	asm("mov $.Lkvm_vmx_return, %0" : "=r"(tmpl));
+	vmcs_writel(HOST_RIP, tmpl); /* 22.2.5 */
+
+	rdmsr(MSR_IA32_SYSENTER_CS, low32, high32);
+	vmcs_write32(HOST_IA32_SYSENTER_CS, low32);
+	rdmsrl(MSR_IA32_SYSENTER_EIP, tmpl);
+	vmcs_writel(HOST_IA32_SYSENTER_EIP, tmpl);   /* 22.2.3 */
+
+	if (vmcs_config.vmexit_ctrl & VM_EXIT_LOAD_IA32_PAT) {
+		rdmsr(MSR_IA32_CR_PAT, low32, high32);
+		vmcs_write64(HOST_IA32_PAT, low32 | ((u64) high32 << 32));
+	}
+}
+
+static void set_cr4_guest_host_mask(struct vcpu_vmx *vmx)
+{
+	vmx->vcpu.arch.cr4_guest_owned_bits = KVM_CR4_GUEST_OWNED_BITS;
+	if (enable_ept)
+		vmx->vcpu.arch.cr4_guest_owned_bits |= X86_CR4_PGE;
+	if (is_guest_mode(&vmx->vcpu))
+		vmx->vcpu.arch.cr4_guest_owned_bits &=
+			~get_vmcs12(&vmx->vcpu)->cr4_guest_host_mask;
+	vmcs_writel(CR4_GUEST_HOST_MASK, ~vmx->vcpu.arch.cr4_guest_owned_bits);
+}
+
+static u32 vmx_exec_control(struct vcpu_vmx *vmx)
+{
+	u32 exec_control = vmcs_config.cpu_based_exec_ctrl;
+	if (!vm_need_tpr_shadow(vmx->vcpu.kvm)) {
+		exec_control &= ~CPU_BASED_TPR_SHADOW;
+#ifdef CONFIG_X86_64
+		exec_control |= CPU_BASED_CR8_STORE_EXITING |
+				CPU_BASED_CR8_LOAD_EXITING;
+#endif
+	}
+	if (!enable_ept)
+		exec_control |= CPU_BASED_CR3_STORE_EXITING |
+				CPU_BASED_CR3_LOAD_EXITING  |
+				CPU_BASED_INVLPG_EXITING;
+	return exec_control;
+}
+
+static u32 vmx_secondary_exec_control(struct vcpu_vmx *vmx)
+{
+	u32 exec_control = vmcs_config.cpu_based_2nd_exec_ctrl;
+	if (!vm_need_virtualize_apic_accesses(vmx->vcpu.kvm))
+		exec_control &= ~SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES;
+	if (vmx->vpid == 0)
+		exec_control &= ~SECONDARY_EXEC_ENABLE_VPID;
+	if (!enable_ept) {
+		exec_control &= ~SECONDARY_EXEC_ENABLE_EPT;
+		enable_unrestricted_guest = 0;
+	}
+	if (!enable_unrestricted_guest)
+		exec_control &= ~SECONDARY_EXEC_UNRESTRICTED_GUEST;
+	if (!ple_gap)
+		exec_control &= ~SECONDARY_EXEC_PAUSE_LOOP_EXITING;
+	return exec_control;
+}
+
+static void ept_set_mmio_spte_mask(void)
+{
+	/*
+	 * EPT Misconfigurations can be generated if the value of bits 2:0
+	 * of an EPT paging-structure entry is 110b (write/execute).
+	 * Also, magic bits (0xffull << 49) is set to quickly identify mmio
+	 * spte.
+	 */
+	kvm_mmu_set_mmio_spte_mask(0xffull << 49 | 0x6ull);
+}
+
+/*
  * Sets up the vmcs for emulated real mode.
  */
 static int vmx_vcpu_setup(struct vcpu_vmx *vmx)
 {
-	u32 host_sysenter_cs, msr_low, msr_high;
-	u32 junk;
-	u64 host_pat;
+#ifdef CONFIG_X86_64
 	unsigned long a;
-	struct desc_ptr dt;
+#endif
 	int i;
-	unsigned long kvm_vmx_return;
-	u32 exec_control;
 
 	/* I/O */
 	vmcs_write64(IO_BITMAP_A, __pa(vmx_io_bitmap_a));
@@ -2747,36 +3628,11 @@ static int vmx_vcpu_setup(struct vcpu_vmx *vmx)
 	vmcs_write32(PIN_BASED_VM_EXEC_CONTROL,
 		vmcs_config.pin_based_exec_ctrl);
 
-	exec_control = vmcs_config.cpu_based_exec_ctrl;
-	if (!vm_need_tpr_shadow(vmx->vcpu.kvm)) {
-		exec_control &= ~CPU_BASED_TPR_SHADOW;
-#ifdef CONFIG_X86_64
-		exec_control |= CPU_BASED_CR8_STORE_EXITING |
-				CPU_BASED_CR8_LOAD_EXITING;
-#endif
-	}
-	if (!enable_ept)
-		exec_control |= CPU_BASED_CR3_STORE_EXITING |
-				CPU_BASED_CR3_LOAD_EXITING  |
-				CPU_BASED_INVLPG_EXITING;
-	vmcs_write32(CPU_BASED_VM_EXEC_CONTROL, exec_control);
+	vmcs_write32(CPU_BASED_VM_EXEC_CONTROL, vmx_exec_control(vmx));
 
 	if (cpu_has_secondary_exec_ctrls()) {
-		exec_control = vmcs_config.cpu_based_2nd_exec_ctrl;
-		if (!vm_need_virtualize_apic_accesses(vmx->vcpu.kvm))
-			exec_control &=
-				~SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES;
-		if (vmx->vpid == 0)
-			exec_control &= ~SECONDARY_EXEC_ENABLE_VPID;
-		if (!enable_ept) {
-			exec_control &= ~SECONDARY_EXEC_ENABLE_EPT;
-			enable_unrestricted_guest = 0;
-		}
-		if (!enable_unrestricted_guest)
-			exec_control &= ~SECONDARY_EXEC_UNRESTRICTED_GUEST;
-		if (!ple_gap)
-			exec_control &= ~SECONDARY_EXEC_PAUSE_LOOP_EXITING;
-		vmcs_write32(SECONDARY_VM_EXEC_CONTROL, exec_control);
+		vmcs_write32(SECONDARY_VM_EXEC_CONTROL,
+				vmx_secondary_exec_control(vmx));
 	}
 
 	if (ple_gap) {
@@ -2784,20 +3640,13 @@ static int vmx_vcpu_setup(struct vcpu_vmx *vmx)
 		vmcs_write32(PLE_WINDOW, ple_window);
 	}
 
-	vmcs_write32(PAGE_FAULT_ERROR_CODE_MASK, !!bypass_guest_pf);
-	vmcs_write32(PAGE_FAULT_ERROR_CODE_MATCH, !!bypass_guest_pf);
+	vmcs_write32(PAGE_FAULT_ERROR_CODE_MASK, 0);
+	vmcs_write32(PAGE_FAULT_ERROR_CODE_MATCH, 0);
 	vmcs_write32(CR3_TARGET_COUNT, 0);           /* 22.2.1 */
 
-	vmcs_writel(HOST_CR0, read_cr0() | X86_CR0_TS);  /* 22.2.3 */
-	vmcs_writel(HOST_CR4, read_cr4());  /* 22.2.3, 22.2.5 */
-	vmcs_writel(HOST_CR3, read_cr3());  /* 22.2.3  FIXME: shadow tables */
-
-	vmcs_write16(HOST_CS_SELECTOR, __KERNEL_CS);  /* 22.2.4 */
-	vmcs_write16(HOST_DS_SELECTOR, __KERNEL_DS);  /* 22.2.4 */
-	vmcs_write16(HOST_ES_SELECTOR, __KERNEL_DS);  /* 22.2.4 */
 	vmcs_write16(HOST_FS_SELECTOR, 0);            /* 22.2.4 */
 	vmcs_write16(HOST_GS_SELECTOR, 0);            /* 22.2.4 */
-	vmcs_write16(HOST_SS_SELECTOR, __KERNEL_DS);  /* 22.2.4 */
+	vmx_set_constant_host_state();
 #ifdef CONFIG_X86_64
 	rdmsrl(MSR_FS_BASE, a);
 	vmcs_writel(HOST_FS_BASE, a); /* 22.2.4 */
@@ -2808,32 +3657,15 @@ static int vmx_vcpu_setup(struct vcpu_vmx *vmx)
 	vmcs_writel(HOST_GS_BASE, 0); /* 22.2.4 */
 #endif
 
-	vmcs_write16(HOST_TR_SELECTOR, GDT_ENTRY_TSS*8);  /* 22.2.4 */
-
-	native_store_idt(&dt);
-	vmcs_writel(HOST_IDTR_BASE, dt.address);   /* 22.2.4 */
-
-	asm("mov $.Lkvm_vmx_return, %0" : "=r"(kvm_vmx_return));
-	vmcs_writel(HOST_RIP, kvm_vmx_return); /* 22.2.5 */
 	vmcs_write32(VM_EXIT_MSR_STORE_COUNT, 0);
 	vmcs_write32(VM_EXIT_MSR_LOAD_COUNT, 0);
 	vmcs_write64(VM_EXIT_MSR_LOAD_ADDR, __pa(vmx->msr_autoload.host));
 	vmcs_write32(VM_ENTRY_MSR_LOAD_COUNT, 0);
 	vmcs_write64(VM_ENTRY_MSR_LOAD_ADDR, __pa(vmx->msr_autoload.guest));
 
-	rdmsr(MSR_IA32_SYSENTER_CS, host_sysenter_cs, junk);
-	vmcs_write32(HOST_IA32_SYSENTER_CS, host_sysenter_cs);
-	rdmsrl(MSR_IA32_SYSENTER_ESP, a);
-	vmcs_writel(HOST_IA32_SYSENTER_ESP, a);   /* 22.2.3 */
-	rdmsrl(MSR_IA32_SYSENTER_EIP, a);
-	vmcs_writel(HOST_IA32_SYSENTER_EIP, a);   /* 22.2.3 */
-
-	if (vmcs_config.vmexit_ctrl & VM_EXIT_LOAD_IA32_PAT) {
-		rdmsr(MSR_IA32_CR_PAT, msr_low, msr_high);
-		host_pat = msr_low | ((u64) msr_high << 32);
-		vmcs_write64(HOST_IA32_PAT, host_pat);
-	}
 	if (vmcs_config.vmentry_ctrl & VM_ENTRY_LOAD_IA32_PAT) {
+		u32 msr_low, msr_high;
+		u64 host_pat;
 		rdmsr(MSR_IA32_CR_PAT, msr_low, msr_high);
 		host_pat = msr_low | ((u64) msr_high << 32);
 		/* Write the default value follow host pat */
@@ -2863,10 +3695,7 @@ static int vmx_vcpu_setup(struct vcpu_vmx *vmx)
 	vmcs_write32(VM_ENTRY_CONTROLS, vmcs_config.vmentry_ctrl);
 
 	vmcs_writel(CR0_GUEST_HOST_MASK, ~0UL);
-	vmx->vcpu.arch.cr4_guest_owned_bits = KVM_CR4_GUEST_OWNED_BITS;
-	if (enable_ept)
-		vmx->vcpu.arch.cr4_guest_owned_bits |= X86_CR4_PGE;
-	vmcs_writel(CR4_GUEST_HOST_MASK, ~vmx->vcpu.arch.cr4_guest_owned_bits);
+	set_cr4_guest_host_mask(vmx);
 
 	kvm_write_tsc(&vmx->vcpu, 0);
 
@@ -2990,9 +3819,25 @@ out:
 	return ret;
 }
 
+/*
+ * In nested virtualization, check if L1 asked to exit on external interrupts.
+ * For most existing hypervisors, this will always return true.
+ */
+static bool nested_exit_on_intr(struct kvm_vcpu *vcpu)
+{
+	return get_vmcs12(vcpu)->pin_based_vm_exec_control &
+		PIN_BASED_EXT_INTR_MASK;
+}
+
 static void enable_irq_window(struct kvm_vcpu *vcpu)
 {
 	u32 cpu_based_vm_exec_control;
+	if (is_guest_mode(vcpu) && nested_exit_on_intr(vcpu))
+		/* We can get here when nested_run_pending caused
+		 * vmx_interrupt_allowed() to return false. In this case, do
+		 * nothing - the interrupt will be injected later.
+		 */
+		return;
 
 	cpu_based_vm_exec_control = vmcs_read32(CPU_BASED_VM_EXEC_CONTROL);
 	cpu_based_vm_exec_control |= CPU_BASED_VIRTUAL_INTR_PENDING;
@@ -3049,6 +3894,9 @@ static void vmx_inject_nmi(struct kvm_vcpu *vcpu)
 {
 	struct vcpu_vmx *vmx = to_vmx(vcpu);
 
+	if (is_guest_mode(vcpu))
+		return;
+
 	if (!cpu_has_virtual_nmis()) {
 		/*
 		 * Tracking the NMI-blocked state in software is built upon
@@ -3115,6 +3963,17 @@ static void vmx_set_nmi_mask(struct kvm_vcpu *vcpu, bool masked)
 
 static int vmx_interrupt_allowed(struct kvm_vcpu *vcpu)
 {
+	if (is_guest_mode(vcpu) && nested_exit_on_intr(vcpu)) {
+		struct vmcs12 *vmcs12;
+		if (to_vmx(vcpu)->nested.nested_run_pending)
+			return 0;
+		nested_vmx_vmexit(vcpu);
+		vmcs12 = get_vmcs12(vcpu);
+		vmcs12->vm_exit_reason = EXIT_REASON_EXTERNAL_INTERRUPT;
+		vmcs12->vm_exit_intr_info = 0;
+		/* fall through to normal code, but now in L1, not L2 */
+	}
+
 	return (vmcs_readl(GUEST_RFLAGS) & X86_EFLAGS_IF) &&
 		!(vmcs_read32(GUEST_INTERRUPTIBILITY_INFO) &
 			(GUEST_INTR_STATE_STI | GUEST_INTR_STATE_MOV_SS));
@@ -3356,6 +4215,58 @@ vmx_patch_hypercall(struct kvm_vcpu *vcpu, unsigned char *hypercall)
 	hypercall[2] = 0xc1;
 }
 
+/* called to set cr0 as approriate for a mov-to-cr0 exit. */
+static int handle_set_cr0(struct kvm_vcpu *vcpu, unsigned long val)
+{
+	if (to_vmx(vcpu)->nested.vmxon &&
+	    ((val & VMXON_CR0_ALWAYSON) != VMXON_CR0_ALWAYSON))
+		return 1;
+
+	if (is_guest_mode(vcpu)) {
+		/*
+		 * We get here when L2 changed cr0 in a way that did not change
+		 * any of L1's shadowed bits (see nested_vmx_exit_handled_cr),
+		 * but did change L0 shadowed bits. This can currently happen
+		 * with the TS bit: L0 may want to leave TS on (for lazy fpu
+		 * loading) while pretending to allow the guest to change it.
+		 */
+		if (kvm_set_cr0(vcpu, (val & vcpu->arch.cr0_guest_owned_bits) |
+			 (vcpu->arch.cr0 & ~vcpu->arch.cr0_guest_owned_bits)))
+			return 1;
+		vmcs_writel(CR0_READ_SHADOW, val);
+		return 0;
+	} else
+		return kvm_set_cr0(vcpu, val);
+}
+
+static int handle_set_cr4(struct kvm_vcpu *vcpu, unsigned long val)
+{
+	if (is_guest_mode(vcpu)) {
+		if (kvm_set_cr4(vcpu, (val & vcpu->arch.cr4_guest_owned_bits) |
+			 (vcpu->arch.cr4 & ~vcpu->arch.cr4_guest_owned_bits)))
+			return 1;
+		vmcs_writel(CR4_READ_SHADOW, val);
+		return 0;
+	} else
+		return kvm_set_cr4(vcpu, val);
+}
+
+/* called to set cr0 as approriate for clts instruction exit. */
+static void handle_clts(struct kvm_vcpu *vcpu)
+{
+	if (is_guest_mode(vcpu)) {
+		/*
+		 * We get here when L2 did CLTS, and L1 didn't shadow CR0.TS
+		 * but we did (!fpu_active). We need to keep GUEST_CR0.TS on,
+		 * just pretend it's off (also in arch.cr0 for fpu_activate).
+		 */
+		vmcs_writel(CR0_READ_SHADOW,
+			vmcs_readl(CR0_READ_SHADOW) & ~X86_CR0_TS);
+		vcpu->arch.cr0 &= ~X86_CR0_TS;
+	} else
+		vmx_set_cr0(vcpu, kvm_read_cr0_bits(vcpu, ~X86_CR0_TS));
+}
+
 static int handle_cr(struct kvm_vcpu *vcpu)
 {
 	unsigned long exit_qualification, val;
@@ -3372,7 +4283,7 @@ static int handle_cr(struct kvm_vcpu *vcpu)
 		trace_kvm_cr_write(cr, val);
 		switch (cr) {
 		case 0:
-			err = kvm_set_cr0(vcpu, val);
+			err = handle_set_cr0(vcpu, val);
 			kvm_complete_insn_gp(vcpu, err);
 			return 1;
 		case 3:
@@ -3380,7 +4291,7 @@ static int handle_cr(struct kvm_vcpu *vcpu)
 			kvm_complete_insn_gp(vcpu, err);
 			return 1;
 		case 4:
-			err = kvm_set_cr4(vcpu, val);
+			err = handle_set_cr4(vcpu, val);
 			kvm_complete_insn_gp(vcpu, err);
 			return 1;
 		case 8: {
@@ -3398,7 +4309,7 @@ static int handle_cr(struct kvm_vcpu *vcpu)
 		};
 		break;
 	case 2: /* clts */
-		vmx_set_cr0(vcpu, kvm_read_cr0_bits(vcpu, ~X86_CR0_TS));
+		handle_clts(vcpu);
 		trace_kvm_cr_write(0, kvm_read_cr0(vcpu));
 		skip_emulated_instruction(vcpu);
 		vmx_fpu_activate(vcpu);
@@ -3574,12 +4485,6 @@ static int handle_vmcall(struct kvm_vcpu *vcpu)
 	return 1;
 }
 
-static int handle_vmx_insn(struct kvm_vcpu *vcpu)
-{
-	kvm_queue_exception(vcpu, UD_VECTOR);
-	return 1;
-}
-
 static int handle_invd(struct kvm_vcpu *vcpu)
 {
 	return emulate_instruction(vcpu, 0) == EMULATE_DONE;
@@ -3777,11 +4682,19 @@ static void ept_misconfig_inspect_spte(struct kvm_vcpu *vcpu, u64 spte,
 static int handle_ept_misconfig(struct kvm_vcpu *vcpu)
 {
 	u64 sptes[4];
-	int nr_sptes, i;
+	int nr_sptes, i, ret;
 	gpa_t gpa;
 
 	gpa = vmcs_read64(GUEST_PHYSICAL_ADDRESS);
 
+	ret = handle_mmio_page_fault_common(vcpu, gpa, true);
+	if (likely(ret == 1))
+		return x86_emulate_instruction(vcpu, gpa, 0, NULL, 0) ==
+					      EMULATE_DONE;
+	if (unlikely(!ret))
+		return 1;
+
+	/* It is the real ept misconfig */
 	printk(KERN_ERR "EPT: Misconfiguration.\n");
 	printk(KERN_ERR "EPT: GPA: 0x%llx\n", gpa);
 
@@ -3866,6 +4779,639 @@ static int handle_invalid_op(struct kvm_vcpu *vcpu)
 }
 
 /*
+ * To run an L2 guest, we need a vmcs02 based on the L1-specified vmcs12.
+ * We could reuse a single VMCS for all the L2 guests, but we also want the
+ * option to allocate a separate vmcs02 for each separate loaded vmcs12 - this
+ * allows keeping them loaded on the processor, and in the future will allow
+ * optimizations where prepare_vmcs02 doesn't need to set all the fields on
+ * every entry if they never change.
+ * So we keep, in vmx->nested.vmcs02_pool, a cache of size VMCS02_POOL_SIZE
+ * (>=0) with a vmcs02 for each recently loaded vmcs12s, most recent first.
+ *
+ * The following functions allocate and free a vmcs02 in this pool.
+ */
+
+/* Get a VMCS from the pool to use as vmcs02 for the current vmcs12. */
+static struct loaded_vmcs *nested_get_current_vmcs02(struct vcpu_vmx *vmx)
+{
+	struct vmcs02_list *item;
+	list_for_each_entry(item, &vmx->nested.vmcs02_pool, list)
+		if (item->vmptr == vmx->nested.current_vmptr) {
+			list_move(&item->list, &vmx->nested.vmcs02_pool);
+			return &item->vmcs02;
+		}
+
+	if (vmx->nested.vmcs02_num >= max(VMCS02_POOL_SIZE, 1)) {
+		/* Recycle the least recently used VMCS. */
+		item = list_entry(vmx->nested.vmcs02_pool.prev,
+			struct vmcs02_list, list);
+		item->vmptr = vmx->nested.current_vmptr;
+		list_move(&item->list, &vmx->nested.vmcs02_pool);
+		return &item->vmcs02;
+	}
+
+	/* Create a new VMCS */
+	item = (struct vmcs02_list *)
+		kmalloc(sizeof(struct vmcs02_list), GFP_KERNEL);
+	if (!item)
+		return NULL;
+	item->vmcs02.vmcs = alloc_vmcs();
+	if (!item->vmcs02.vmcs) {
+		kfree(item);
+		return NULL;
+	}
+	loaded_vmcs_init(&item->vmcs02);
+	item->vmptr = vmx->nested.current_vmptr;
+	list_add(&(item->list), &(vmx->nested.vmcs02_pool));
+	vmx->nested.vmcs02_num++;
+	return &item->vmcs02;
+}
+
+/* Free and remove from pool a vmcs02 saved for a vmcs12 (if there is one) */
+static void nested_free_vmcs02(struct vcpu_vmx *vmx, gpa_t vmptr)
+{
+	struct vmcs02_list *item;
+	list_for_each_entry(item, &vmx->nested.vmcs02_pool, list)
+		if (item->vmptr == vmptr) {
+			free_loaded_vmcs(&item->vmcs02);
+			list_del(&item->list);
+			kfree(item);
+			vmx->nested.vmcs02_num--;
+			return;
+		}
+}
+
+/*
+ * Free all VMCSs saved for this vcpu, except the one pointed by
+ * vmx->loaded_vmcs. These include the VMCSs in vmcs02_pool (except the one
+ * currently used, if running L2), and vmcs01 when running L2.
+ */
+static void nested_free_all_saved_vmcss(struct vcpu_vmx *vmx)
+{
+	struct vmcs02_list *item, *n;
+	list_for_each_entry_safe(item, n, &vmx->nested.vmcs02_pool, list) {
+		if (vmx->loaded_vmcs != &item->vmcs02)
+			free_loaded_vmcs(&item->vmcs02);
+		list_del(&item->list);
+		kfree(item);
+	}
+	vmx->nested.vmcs02_num = 0;
+
+	if (vmx->loaded_vmcs != &vmx->vmcs01)
+		free_loaded_vmcs(&vmx->vmcs01);
+}
+
+/*
+ * Emulate the VMXON instruction.
+ * Currently, we just remember that VMX is active, and do not save or even
+ * inspect the argument to VMXON (the so-called "VMXON pointer") because we
+ * do not currently need to store anything in that guest-allocated memory
+ * region. Consequently, VMCLEAR and VMPTRLD also do not verify that the their
+ * argument is different from the VMXON pointer (which the spec says they do).
+ */
+static int handle_vmon(struct kvm_vcpu *vcpu)
+{
+	struct kvm_segment cs;
+	struct vcpu_vmx *vmx = to_vmx(vcpu);
+
+	/* The Intel VMX Instruction Reference lists a bunch of bits that
+	 * are prerequisite to running VMXON, most notably cr4.VMXE must be
+	 * set to 1 (see vmx_set_cr4() for when we allow the guest to set this).
+	 * Otherwise, we should fail with #UD. We test these now:
+	 */
+	if (!kvm_read_cr4_bits(vcpu, X86_CR4_VMXE) ||
+	    !kvm_read_cr0_bits(vcpu, X86_CR0_PE) ||
+	    (vmx_get_rflags(vcpu) & X86_EFLAGS_VM)) {
+		kvm_queue_exception(vcpu, UD_VECTOR);
+		return 1;
+	}
+
+	vmx_get_segment(vcpu, &cs, VCPU_SREG_CS);
+	if (is_long_mode(vcpu) && !cs.l) {
+		kvm_queue_exception(vcpu, UD_VECTOR);
+		return 1;
+	}
+
+	if (vmx_get_cpl(vcpu)) {
+		kvm_inject_gp(vcpu, 0);
+		return 1;
+	}
+
+	INIT_LIST_HEAD(&(vmx->nested.vmcs02_pool));
+	vmx->nested.vmcs02_num = 0;
+
+	vmx->nested.vmxon = true;
+
+	skip_emulated_instruction(vcpu);
+	return 1;
+}
+
+/*
+ * Intel's VMX Instruction Reference specifies a common set of prerequisites
+ * for running VMX instructions (except VMXON, whose prerequisites are
+ * slightly different). It also specifies what exception to inject otherwise.
+ */
+static int nested_vmx_check_permission(struct kvm_vcpu *vcpu)
+{
+	struct kvm_segment cs;
+	struct vcpu_vmx *vmx = to_vmx(vcpu);
+
+	if (!vmx->nested.vmxon) {
+		kvm_queue_exception(vcpu, UD_VECTOR);
+		return 0;
+	}
+
+	vmx_get_segment(vcpu, &cs, VCPU_SREG_CS);
+	if ((vmx_get_rflags(vcpu) & X86_EFLAGS_VM) ||
+	    (is_long_mode(vcpu) && !cs.l)) {
+		kvm_queue_exception(vcpu, UD_VECTOR);
+		return 0;
+	}
+
+	if (vmx_get_cpl(vcpu)) {
+		kvm_inject_gp(vcpu, 0);
+		return 0;
+	}
+
+	return 1;
+}
+
+/*
+ * Free whatever needs to be freed from vmx->nested when L1 goes down, or
+ * just stops using VMX.
+ */
+static void free_nested(struct vcpu_vmx *vmx)
+{
+	if (!vmx->nested.vmxon)
+		return;
+	vmx->nested.vmxon = false;
+	if (vmx->nested.current_vmptr != -1ull) {
+		kunmap(vmx->nested.current_vmcs12_page);
+		nested_release_page(vmx->nested.current_vmcs12_page);
+		vmx->nested.current_vmptr = -1ull;
+		vmx->nested.current_vmcs12 = NULL;
+	}
+	/* Unpin physical memory we referred to in current vmcs02 */
+	if (vmx->nested.apic_access_page) {
+		nested_release_page(vmx->nested.apic_access_page);
+		vmx->nested.apic_access_page = 0;
+	}
+
+	nested_free_all_saved_vmcss(vmx);
+}
+
+/* Emulate the VMXOFF instruction */
+static int handle_vmoff(struct kvm_vcpu *vcpu)
+{
+	if (!nested_vmx_check_permission(vcpu))
+		return 1;
+	free_nested(to_vmx(vcpu));
+	skip_emulated_instruction(vcpu);
+	return 1;
+}
+
+/*
+ * Decode the memory-address operand of a vmx instruction, as recorded on an
+ * exit caused by such an instruction (run by a guest hypervisor).
+ * On success, returns 0. When the operand is invalid, returns 1 and throws
+ * #UD or #GP.
+ */
+static int get_vmx_mem_address(struct kvm_vcpu *vcpu,
+				 unsigned long exit_qualification,
+				 u32 vmx_instruction_info, gva_t *ret)
+{
+	/*
+	 * According to Vol. 3B, "Information for VM Exits Due to Instruction
+	 * Execution", on an exit, vmx_instruction_info holds most of the
+	 * addressing components of the operand. Only the displacement part
+	 * is put in exit_qualification (see 3B, "Basic VM-Exit Information").
+	 * For how an actual address is calculated from all these components,
+	 * refer to Vol. 1, "Operand Addressing".
+	 */
+	int  scaling = vmx_instruction_info & 3;
+	int  addr_size = (vmx_instruction_info >> 7) & 7;
+	bool is_reg = vmx_instruction_info & (1u << 10);
+	int  seg_reg = (vmx_instruction_info >> 15) & 7;
+	int  index_reg = (vmx_instruction_info >> 18) & 0xf;
+	bool index_is_valid = !(vmx_instruction_info & (1u << 22));
+	int  base_reg       = (vmx_instruction_info >> 23) & 0xf;
+	bool base_is_valid  = !(vmx_instruction_info & (1u << 27));
+
+	if (is_reg) {
+		kvm_queue_exception(vcpu, UD_VECTOR);
+		return 1;
+	}
+
+	/* Addr = segment_base + offset */
+	/* offset = base + [index * scale] + displacement */
+	*ret = vmx_get_segment_base(vcpu, seg_reg);
+	if (base_is_valid)
+		*ret += kvm_register_read(vcpu, base_reg);
+	if (index_is_valid)
+		*ret += kvm_register_read(vcpu, index_reg)<<scaling;
+	*ret += exit_qualification; /* holds the displacement */
+
+	if (addr_size == 1) /* 32 bit */
+		*ret &= 0xffffffff;
+
+	/*
+	 * TODO: throw #GP (and return 1) in various cases that the VM*
+	 * instructions require it - e.g., offset beyond segment limit,
+	 * unusable or unreadable/unwritable segment, non-canonical 64-bit
+	 * address, and so on. Currently these are not checked.
+	 */
+	return 0;
+}
+
+/*
+ * The following 3 functions, nested_vmx_succeed()/failValid()/failInvalid(),
+ * set the success or error code of an emulated VMX instruction, as specified
+ * by Vol 2B, VMX Instruction Reference, "Conventions".
+ */
+static void nested_vmx_succeed(struct kvm_vcpu *vcpu)
+{
+	vmx_set_rflags(vcpu, vmx_get_rflags(vcpu)
+			& ~(X86_EFLAGS_CF | X86_EFLAGS_PF | X86_EFLAGS_AF |
+			    X86_EFLAGS_ZF | X86_EFLAGS_SF | X86_EFLAGS_OF));
+}
+
+static void nested_vmx_failInvalid(struct kvm_vcpu *vcpu)
+{
+	vmx_set_rflags(vcpu, (vmx_get_rflags(vcpu)
+			& ~(X86_EFLAGS_PF | X86_EFLAGS_AF | X86_EFLAGS_ZF |
+			    X86_EFLAGS_SF | X86_EFLAGS_OF))
+			| X86_EFLAGS_CF);
+}
+
+static void nested_vmx_failValid(struct kvm_vcpu *vcpu,
+					u32 vm_instruction_error)
+{
+	if (to_vmx(vcpu)->nested.current_vmptr == -1ull) {
+		/*
+		 * failValid writes the error number to the current VMCS, which
+		 * can't be done there isn't a current VMCS.
+		 */
+		nested_vmx_failInvalid(vcpu);
+		return;
+	}
+	vmx_set_rflags(vcpu, (vmx_get_rflags(vcpu)
+			& ~(X86_EFLAGS_CF | X86_EFLAGS_PF | X86_EFLAGS_AF |
+			    X86_EFLAGS_SF | X86_EFLAGS_OF))
+			| X86_EFLAGS_ZF);
+	get_vmcs12(vcpu)->vm_instruction_error = vm_instruction_error;
+}
+
+/* Emulate the VMCLEAR instruction */
+static int handle_vmclear(struct kvm_vcpu *vcpu)
+{
+	struct vcpu_vmx *vmx = to_vmx(vcpu);
+	gva_t gva;
+	gpa_t vmptr;
+	struct vmcs12 *vmcs12;
+	struct page *page;
+	struct x86_exception e;
+
+	if (!nested_vmx_check_permission(vcpu))
+		return 1;
+
+	if (get_vmx_mem_address(vcpu, vmcs_readl(EXIT_QUALIFICATION),
+			vmcs_read32(VMX_INSTRUCTION_INFO), &gva))
+		return 1;
+
+	if (kvm_read_guest_virt(&vcpu->arch.emulate_ctxt, gva, &vmptr,
+				sizeof(vmptr), &e)) {
+		kvm_inject_page_fault(vcpu, &e);
+		return 1;
+	}
+
+	if (!IS_ALIGNED(vmptr, PAGE_SIZE)) {
+		nested_vmx_failValid(vcpu, VMXERR_VMCLEAR_INVALID_ADDRESS);
+		skip_emulated_instruction(vcpu);
+		return 1;
+	}
+
+	if (vmptr == vmx->nested.current_vmptr) {
+		kunmap(vmx->nested.current_vmcs12_page);
+		nested_release_page(vmx->nested.current_vmcs12_page);
+		vmx->nested.current_vmptr = -1ull;
+		vmx->nested.current_vmcs12 = NULL;
+	}
+
+	page = nested_get_page(vcpu, vmptr);
+	if (page == NULL) {
+		/*
+		 * For accurate processor emulation, VMCLEAR beyond available
+		 * physical memory should do nothing at all. However, it is
+		 * possible that a nested vmx bug, not a guest hypervisor bug,
+		 * resulted in this case, so let's shut down before doing any
+		 * more damage:
+		 */
+		kvm_make_request(KVM_REQ_TRIPLE_FAULT, vcpu);
+		return 1;
+	}
+	vmcs12 = kmap(page);
+	vmcs12->launch_state = 0;
+	kunmap(page);
+	nested_release_page(page);
+
+	nested_free_vmcs02(vmx, vmptr);
+
+	skip_emulated_instruction(vcpu);
+	nested_vmx_succeed(vcpu);
+	return 1;
+}
+
+static int nested_vmx_run(struct kvm_vcpu *vcpu, bool launch);
+
+/* Emulate the VMLAUNCH instruction */
+static int handle_vmlaunch(struct kvm_vcpu *vcpu)
+{
+	return nested_vmx_run(vcpu, true);
+}
+
+/* Emulate the VMRESUME instruction */
+static int handle_vmresume(struct kvm_vcpu *vcpu)
+{
+
+	return nested_vmx_run(vcpu, false);
+}
+
+enum vmcs_field_type {
+	VMCS_FIELD_TYPE_U16 = 0,
+	VMCS_FIELD_TYPE_U64 = 1,
+	VMCS_FIELD_TYPE_U32 = 2,
+	VMCS_FIELD_TYPE_NATURAL_WIDTH = 3
+};
+
+static inline int vmcs_field_type(unsigned long field)
+{
+	if (0x1 & field)	/* the *_HIGH fields are all 32 bit */
+		return VMCS_FIELD_TYPE_U32;
+	return (field >> 13) & 0x3 ;
+}
+
+static inline int vmcs_field_readonly(unsigned long field)
+{
+	return (((field >> 10) & 0x3) == 1);
+}
+
+/*
+ * Read a vmcs12 field. Since these can have varying lengths and we return
+ * one type, we chose the biggest type (u64) and zero-extend the return value
+ * to that size. Note that the caller, handle_vmread, might need to use only
+ * some of the bits we return here (e.g., on 32-bit guests, only 32 bits of
+ * 64-bit fields are to be returned).
+ */
+static inline bool vmcs12_read_any(struct kvm_vcpu *vcpu,
+					unsigned long field, u64 *ret)
+{
+	short offset = vmcs_field_to_offset(field);
+	char *p;
+
+	if (offset < 0)
+		return 0;
+
+	p = ((char *)(get_vmcs12(vcpu))) + offset;
+
+	switch (vmcs_field_type(field)) {
+	case VMCS_FIELD_TYPE_NATURAL_WIDTH:
+		*ret = *((natural_width *)p);
+		return 1;
+	case VMCS_FIELD_TYPE_U16:
+		*ret = *((u16 *)p);
+		return 1;
+	case VMCS_FIELD_TYPE_U32:
+		*ret = *((u32 *)p);
+		return 1;
+	case VMCS_FIELD_TYPE_U64:
+		*ret = *((u64 *)p);
+		return 1;
+	default:
+		return 0; /* can never happen. */
+	}
+}
+
+/*
+ * VMX instructions which assume a current vmcs12 (i.e., that VMPTRLD was
+ * used before) all generate the same failure when it is missing.
+ */
+static int nested_vmx_check_vmcs12(struct kvm_vcpu *vcpu)
+{
+	struct vcpu_vmx *vmx = to_vmx(vcpu);
+	if (vmx->nested.current_vmptr == -1ull) {
+		nested_vmx_failInvalid(vcpu);
+		skip_emulated_instruction(vcpu);
+		return 0;
+	}
+	return 1;
+}
+
+static int handle_vmread(struct kvm_vcpu *vcpu)
+{
+	unsigned long field;
+	u64 field_value;
+	unsigned long exit_qualification = vmcs_readl(EXIT_QUALIFICATION);
+	u32 vmx_instruction_info = vmcs_read32(VMX_INSTRUCTION_INFO);
+	gva_t gva = 0;
+
+	if (!nested_vmx_check_permission(vcpu) ||
+	    !nested_vmx_check_vmcs12(vcpu))
+		return 1;
+
+	/* Decode instruction info and find the field to read */
+	field = kvm_register_read(vcpu, (((vmx_instruction_info) >> 28) & 0xf));
+	/* Read the field, zero-extended to a u64 field_value */
+	if (!vmcs12_read_any(vcpu, field, &field_value)) {
+		nested_vmx_failValid(vcpu, VMXERR_UNSUPPORTED_VMCS_COMPONENT);
+		skip_emulated_instruction(vcpu);
+		return 1;
+	}
+	/*
+	 * Now copy part of this value to register or memory, as requested.
+	 * Note that the number of bits actually copied is 32 or 64 depending
+	 * on the guest's mode (32 or 64 bit), not on the given field's length.
+	 */
+	if (vmx_instruction_info & (1u << 10)) {
+		kvm_register_write(vcpu, (((vmx_instruction_info) >> 3) & 0xf),
+			field_value);
+	} else {
+		if (get_vmx_mem_address(vcpu, exit_qualification,
+				vmx_instruction_info, &gva))
+			return 1;
+		/* _system ok, as nested_vmx_check_permission verified cpl=0 */
+		kvm_write_guest_virt_system(&vcpu->arch.emulate_ctxt, gva,
+			     &field_value, (is_long_mode(vcpu) ? 8 : 4), NULL);
+	}
+
+	nested_vmx_succeed(vcpu);
+	skip_emulated_instruction(vcpu);
+	return 1;
+}
+
+
+static int handle_vmwrite(struct kvm_vcpu *vcpu)
+{
+	unsigned long field;
+	gva_t gva;
+	unsigned long exit_qualification = vmcs_readl(EXIT_QUALIFICATION);
+	u32 vmx_instruction_info = vmcs_read32(VMX_INSTRUCTION_INFO);
+	char *p;
+	short offset;
+	/* The value to write might be 32 or 64 bits, depending on L1's long
+	 * mode, and eventually we need to write that into a field of several
+	 * possible lengths. The code below first zero-extends the value to 64
+	 * bit (field_value), and then copies only the approriate number of
+	 * bits into the vmcs12 field.
+	 */
+	u64 field_value = 0;
+	struct x86_exception e;
+
+	if (!nested_vmx_check_permission(vcpu) ||
+	    !nested_vmx_check_vmcs12(vcpu))
+		return 1;
+
+	if (vmx_instruction_info & (1u << 10))
+		field_value = kvm_register_read(vcpu,
+			(((vmx_instruction_info) >> 3) & 0xf));
+	else {
+		if (get_vmx_mem_address(vcpu, exit_qualification,
+				vmx_instruction_info, &gva))
+			return 1;
+		if (kvm_read_guest_virt(&vcpu->arch.emulate_ctxt, gva,
+			   &field_value, (is_long_mode(vcpu) ? 8 : 4), &e)) {
+			kvm_inject_page_fault(vcpu, &e);
+			return 1;
+		}
+	}
+
+
+	field = kvm_register_read(vcpu, (((vmx_instruction_info) >> 28) & 0xf));
+	if (vmcs_field_readonly(field)) {
+		nested_vmx_failValid(vcpu,
+			VMXERR_VMWRITE_READ_ONLY_VMCS_COMPONENT);
+		skip_emulated_instruction(vcpu);
+		return 1;
+	}
+
+	offset = vmcs_field_to_offset(field);
+	if (offset < 0) {
+		nested_vmx_failValid(vcpu, VMXERR_UNSUPPORTED_VMCS_COMPONENT);
+		skip_emulated_instruction(vcpu);
+		return 1;
+	}
+	p = ((char *) get_vmcs12(vcpu)) + offset;
+
+	switch (vmcs_field_type(field)) {
+	case VMCS_FIELD_TYPE_U16:
+		*(u16 *)p = field_value;
+		break;
+	case VMCS_FIELD_TYPE_U32:
+		*(u32 *)p = field_value;
+		break;
+	case VMCS_FIELD_TYPE_U64:
+		*(u64 *)p = field_value;
+		break;
+	case VMCS_FIELD_TYPE_NATURAL_WIDTH:
+		*(natural_width *)p = field_value;
+		break;
+	default:
+		nested_vmx_failValid(vcpu, VMXERR_UNSUPPORTED_VMCS_COMPONENT);
+		skip_emulated_instruction(vcpu);
+		return 1;
+	}
+
+	nested_vmx_succeed(vcpu);
+	skip_emulated_instruction(vcpu);
+	return 1;
+}
+
+/* Emulate the VMPTRLD instruction */
+static int handle_vmptrld(struct kvm_vcpu *vcpu)
+{
+	struct vcpu_vmx *vmx = to_vmx(vcpu);
+	gva_t gva;
+	gpa_t vmptr;
+	struct x86_exception e;
+
+	if (!nested_vmx_check_permission(vcpu))
+		return 1;
+
+	if (get_vmx_mem_address(vcpu, vmcs_readl(EXIT_QUALIFICATION),
+			vmcs_read32(VMX_INSTRUCTION_INFO), &gva))
+		return 1;
+
+	if (kvm_read_guest_virt(&vcpu->arch.emulate_ctxt, gva, &vmptr,
+				sizeof(vmptr), &e)) {
+		kvm_inject_page_fault(vcpu, &e);
+		return 1;
+	}
+
+	if (!IS_ALIGNED(vmptr, PAGE_SIZE)) {
+		nested_vmx_failValid(vcpu, VMXERR_VMPTRLD_INVALID_ADDRESS);
+		skip_emulated_instruction(vcpu);
+		return 1;
+	}
+
+	if (vmx->nested.current_vmptr != vmptr) {
+		struct vmcs12 *new_vmcs12;
+		struct page *page;
+		page = nested_get_page(vcpu, vmptr);
+		if (page == NULL) {
+			nested_vmx_failInvalid(vcpu);
+			skip_emulated_instruction(vcpu);
+			return 1;
+		}
+		new_vmcs12 = kmap(page);
+		if (new_vmcs12->revision_id != VMCS12_REVISION) {
+			kunmap(page);
+			nested_release_page_clean(page);
+			nested_vmx_failValid(vcpu,
+				VMXERR_VMPTRLD_INCORRECT_VMCS_REVISION_ID);
+			skip_emulated_instruction(vcpu);
+			return 1;
+		}
+		if (vmx->nested.current_vmptr != -1ull) {
+			kunmap(vmx->nested.current_vmcs12_page);
+			nested_release_page(vmx->nested.current_vmcs12_page);
+		}
+
+		vmx->nested.current_vmptr = vmptr;
+		vmx->nested.current_vmcs12 = new_vmcs12;
+		vmx->nested.current_vmcs12_page = page;
+	}
+
+	nested_vmx_succeed(vcpu);
+	skip_emulated_instruction(vcpu);
+	return 1;
+}
+
+/* Emulate the VMPTRST instruction */
+static int handle_vmptrst(struct kvm_vcpu *vcpu)
+{
+	unsigned long exit_qualification = vmcs_readl(EXIT_QUALIFICATION);
+	u32 vmx_instruction_info = vmcs_read32(VMX_INSTRUCTION_INFO);
+	gva_t vmcs_gva;
+	struct x86_exception e;
+
+	if (!nested_vmx_check_permission(vcpu))
+		return 1;
+
+	if (get_vmx_mem_address(vcpu, exit_qualification,
+			vmx_instruction_info, &vmcs_gva))
+		return 1;
+	/* ok to use *_system, as nested_vmx_check_permission verified cpl=0 */
+	if (kvm_write_guest_virt_system(&vcpu->arch.emulate_ctxt, vmcs_gva,
+				 (void *)&to_vmx(vcpu)->nested.current_vmptr,
+				 sizeof(u64), &e)) {
+		kvm_inject_page_fault(vcpu, &e);
+		return 1;
+	}
+	nested_vmx_succeed(vcpu);
+	skip_emulated_instruction(vcpu);
+	return 1;
+}
+
+/*
  * The exit handlers return 1 if the exit was handled fully and guest execution
  * may resume.  Otherwise they set the kvm_run parameter to indicate what needs
  * to be done to userspace and return 0.
@@ -3886,15 +5432,15 @@ static int (*kvm_vmx_exit_handlers[])(struct kvm_vcpu *vcpu) = {
 	[EXIT_REASON_INVD]		      = handle_invd,
 	[EXIT_REASON_INVLPG]		      = handle_invlpg,
 	[EXIT_REASON_VMCALL]                  = handle_vmcall,
-	[EXIT_REASON_VMCLEAR]	              = handle_vmx_insn,
-	[EXIT_REASON_VMLAUNCH]                = handle_vmx_insn,
-	[EXIT_REASON_VMPTRLD]                 = handle_vmx_insn,
-	[EXIT_REASON_VMPTRST]                 = handle_vmx_insn,
-	[EXIT_REASON_VMREAD]                  = handle_vmx_insn,
-	[EXIT_REASON_VMRESUME]                = handle_vmx_insn,
-	[EXIT_REASON_VMWRITE]                 = handle_vmx_insn,
-	[EXIT_REASON_VMOFF]                   = handle_vmx_insn,
-	[EXIT_REASON_VMON]                    = handle_vmx_insn,
+	[EXIT_REASON_VMCLEAR]	              = handle_vmclear,
+	[EXIT_REASON_VMLAUNCH]                = handle_vmlaunch,
+	[EXIT_REASON_VMPTRLD]                 = handle_vmptrld,
+	[EXIT_REASON_VMPTRST]                 = handle_vmptrst,
+	[EXIT_REASON_VMREAD]                  = handle_vmread,
+	[EXIT_REASON_VMRESUME]                = handle_vmresume,
+	[EXIT_REASON_VMWRITE]                 = handle_vmwrite,
+	[EXIT_REASON_VMOFF]                   = handle_vmoff,
+	[EXIT_REASON_VMON]                    = handle_vmon,
 	[EXIT_REASON_TPR_BELOW_THRESHOLD]     = handle_tpr_below_threshold,
 	[EXIT_REASON_APIC_ACCESS]             = handle_apic_access,
 	[EXIT_REASON_WBINVD]                  = handle_wbinvd,
@@ -3911,6 +5457,229 @@ static int (*kvm_vmx_exit_handlers[])(struct kvm_vcpu *vcpu) = {
 static const int kvm_vmx_max_exit_handlers =
 	ARRAY_SIZE(kvm_vmx_exit_handlers);
 
+/*
+ * Return 1 if we should exit from L2 to L1 to handle an MSR access access,
+ * rather than handle it ourselves in L0. I.e., check whether L1 expressed
+ * disinterest in the current event (read or write a specific MSR) by using an
+ * MSR bitmap. This may be the case even when L0 doesn't use MSR bitmaps.
+ */
+static bool nested_vmx_exit_handled_msr(struct kvm_vcpu *vcpu,
+	struct vmcs12 *vmcs12, u32 exit_reason)
+{
+	u32 msr_index = vcpu->arch.regs[VCPU_REGS_RCX];
+	gpa_t bitmap;
+
+	if (!nested_cpu_has(get_vmcs12(vcpu), CPU_BASED_USE_MSR_BITMAPS))
+		return 1;
+
+	/*
+	 * The MSR_BITMAP page is divided into four 1024-byte bitmaps,
+	 * for the four combinations of read/write and low/high MSR numbers.
+	 * First we need to figure out which of the four to use:
+	 */
+	bitmap = vmcs12->msr_bitmap;
+	if (exit_reason == EXIT_REASON_MSR_WRITE)
+		bitmap += 2048;
+	if (msr_index >= 0xc0000000) {
+		msr_index -= 0xc0000000;
+		bitmap += 1024;
+	}
+
+	/* Then read the msr_index'th bit from this bitmap: */
+	if (msr_index < 1024*8) {
+		unsigned char b;
+		kvm_read_guest(vcpu->kvm, bitmap + msr_index/8, &b, 1);
+		return 1 & (b >> (msr_index & 7));
+	} else
+		return 1; /* let L1 handle the wrong parameter */
+}
+
+/*
+ * Return 1 if we should exit from L2 to L1 to handle a CR access exit,
+ * rather than handle it ourselves in L0. I.e., check if L1 wanted to
+ * intercept (via guest_host_mask etc.) the current event.
+ */
+static bool nested_vmx_exit_handled_cr(struct kvm_vcpu *vcpu,
+	struct vmcs12 *vmcs12)
+{
+	unsigned long exit_qualification = vmcs_readl(EXIT_QUALIFICATION);
+	int cr = exit_qualification & 15;
+	int reg = (exit_qualification >> 8) & 15;
+	unsigned long val = kvm_register_read(vcpu, reg);
+
+	switch ((exit_qualification >> 4) & 3) {
+	case 0: /* mov to cr */
+		switch (cr) {
+		case 0:
+			if (vmcs12->cr0_guest_host_mask &
+			    (val ^ vmcs12->cr0_read_shadow))
+				return 1;
+			break;
+		case 3:
+			if ((vmcs12->cr3_target_count >= 1 &&
+					vmcs12->cr3_target_value0 == val) ||
+				(vmcs12->cr3_target_count >= 2 &&
+					vmcs12->cr3_target_value1 == val) ||
+				(vmcs12->cr3_target_count >= 3 &&
+					vmcs12->cr3_target_value2 == val) ||
+				(vmcs12->cr3_target_count >= 4 &&
+					vmcs12->cr3_target_value3 == val))
+				return 0;
+			if (nested_cpu_has(vmcs12, CPU_BASED_CR3_LOAD_EXITING))
+				return 1;
+			break;
+		case 4:
+			if (vmcs12->cr4_guest_host_mask &
+			    (vmcs12->cr4_read_shadow ^ val))
+				return 1;
+			break;
+		case 8:
+			if (nested_cpu_has(vmcs12, CPU_BASED_CR8_LOAD_EXITING))
+				return 1;
+			break;
+		}
+		break;
+	case 2: /* clts */
+		if ((vmcs12->cr0_guest_host_mask & X86_CR0_TS) &&
+		    (vmcs12->cr0_read_shadow & X86_CR0_TS))
+			return 1;
+		break;
+	case 1: /* mov from cr */
+		switch (cr) {
+		case 3:
+			if (vmcs12->cpu_based_vm_exec_control &
+			    CPU_BASED_CR3_STORE_EXITING)
+				return 1;
+			break;
+		case 8:
+			if (vmcs12->cpu_based_vm_exec_control &
+			    CPU_BASED_CR8_STORE_EXITING)
+				return 1;
+			break;
+		}
+		break;
+	case 3: /* lmsw */
+		/*
+		 * lmsw can change bits 1..3 of cr0, and only set bit 0 of
+		 * cr0. Other attempted changes are ignored, with no exit.
+		 */
+		if (vmcs12->cr0_guest_host_mask & 0xe &
+		    (val ^ vmcs12->cr0_read_shadow))
+			return 1;
+		if ((vmcs12->cr0_guest_host_mask & 0x1) &&
+		    !(vmcs12->cr0_read_shadow & 0x1) &&
+		    (val & 0x1))
+			return 1;
+		break;
+	}
+	return 0;
+}
+
+/*
+ * Return 1 if we should exit from L2 to L1 to handle an exit, or 0 if we
+ * should handle it ourselves in L0 (and then continue L2). Only call this
+ * when in is_guest_mode (L2).
+ */
+static bool nested_vmx_exit_handled(struct kvm_vcpu *vcpu)
+{
+	u32 exit_reason = vmcs_read32(VM_EXIT_REASON);
+	u32 intr_info = vmcs_read32(VM_EXIT_INTR_INFO);
+	struct vcpu_vmx *vmx = to_vmx(vcpu);
+	struct vmcs12 *vmcs12 = get_vmcs12(vcpu);
+
+	if (vmx->nested.nested_run_pending)
+		return 0;
+
+	if (unlikely(vmx->fail)) {
+		printk(KERN_INFO "%s failed vm entry %x\n",
+		       __func__, vmcs_read32(VM_INSTRUCTION_ERROR));
+		return 1;
+	}
+
+	switch (exit_reason) {
+	case EXIT_REASON_EXCEPTION_NMI:
+		if (!is_exception(intr_info))
+			return 0;
+		else if (is_page_fault(intr_info))
+			return enable_ept;
+		return vmcs12->exception_bitmap &
+				(1u << (intr_info & INTR_INFO_VECTOR_MASK));
+	case EXIT_REASON_EXTERNAL_INTERRUPT:
+		return 0;
+	case EXIT_REASON_TRIPLE_FAULT:
+		return 1;
+	case EXIT_REASON_PENDING_INTERRUPT:
+	case EXIT_REASON_NMI_WINDOW:
+		/*
+		 * prepare_vmcs02() set the CPU_BASED_VIRTUAL_INTR_PENDING bit
+		 * (aka Interrupt Window Exiting) only when L1 turned it on,
+		 * so if we got a PENDING_INTERRUPT exit, this must be for L1.
+		 * Same for NMI Window Exiting.
+		 */
+		return 1;
+	case EXIT_REASON_TASK_SWITCH:
+		return 1;
+	case EXIT_REASON_CPUID:
+		return 1;
+	case EXIT_REASON_HLT:
+		return nested_cpu_has(vmcs12, CPU_BASED_HLT_EXITING);
+	case EXIT_REASON_INVD:
+		return 1;
+	case EXIT_REASON_INVLPG:
+		return nested_cpu_has(vmcs12, CPU_BASED_INVLPG_EXITING);
+	case EXIT_REASON_RDPMC:
+		return nested_cpu_has(vmcs12, CPU_BASED_RDPMC_EXITING);
+	case EXIT_REASON_RDTSC:
+		return nested_cpu_has(vmcs12, CPU_BASED_RDTSC_EXITING);
+	case EXIT_REASON_VMCALL: case EXIT_REASON_VMCLEAR:
+	case EXIT_REASON_VMLAUNCH: case EXIT_REASON_VMPTRLD:
+	case EXIT_REASON_VMPTRST: case EXIT_REASON_VMREAD:
+	case EXIT_REASON_VMRESUME: case EXIT_REASON_VMWRITE:
+	case EXIT_REASON_VMOFF: case EXIT_REASON_VMON:
+		/*
+		 * VMX instructions trap unconditionally. This allows L1 to
+		 * emulate them for its L2 guest, i.e., allows 3-level nesting!
+		 */
+		return 1;
+	case EXIT_REASON_CR_ACCESS:
+		return nested_vmx_exit_handled_cr(vcpu, vmcs12);
+	case EXIT_REASON_DR_ACCESS:
+		return nested_cpu_has(vmcs12, CPU_BASED_MOV_DR_EXITING);
+	case EXIT_REASON_IO_INSTRUCTION:
+		/* TODO: support IO bitmaps */
+		return 1;
+	case EXIT_REASON_MSR_READ:
+	case EXIT_REASON_MSR_WRITE:
+		return nested_vmx_exit_handled_msr(vcpu, vmcs12, exit_reason);
+	case EXIT_REASON_INVALID_STATE:
+		return 1;
+	case EXIT_REASON_MWAIT_INSTRUCTION:
+		return nested_cpu_has(vmcs12, CPU_BASED_MWAIT_EXITING);
+	case EXIT_REASON_MONITOR_INSTRUCTION:
+		return nested_cpu_has(vmcs12, CPU_BASED_MONITOR_EXITING);
+	case EXIT_REASON_PAUSE_INSTRUCTION:
+		return nested_cpu_has(vmcs12, CPU_BASED_PAUSE_EXITING) ||
+			nested_cpu_has2(vmcs12,
+				SECONDARY_EXEC_PAUSE_LOOP_EXITING);
+	case EXIT_REASON_MCE_DURING_VMENTRY:
+		return 0;
+	case EXIT_REASON_TPR_BELOW_THRESHOLD:
+		return 1;
+	case EXIT_REASON_APIC_ACCESS:
+		return nested_cpu_has2(vmcs12,
+			SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES);
+	case EXIT_REASON_EPT_VIOLATION:
+	case EXIT_REASON_EPT_MISCONFIG:
+		return 0;
+	case EXIT_REASON_WBINVD:
+		return nested_cpu_has2(vmcs12, SECONDARY_EXEC_WBINVD_EXITING);
+	case EXIT_REASON_XSETBV:
+		return 1;
+	default:
+		return 1;
+	}
+}
+
 static void vmx_get_exit_info(struct kvm_vcpu *vcpu, u64 *info1, u64 *info2)
 {
 	*info1 = vmcs_readl(EXIT_QUALIFICATION);
@@ -3933,6 +5702,25 @@ static int vmx_handle_exit(struct kvm_vcpu *vcpu)
 	if (vmx->emulation_required && emulate_invalid_guest_state)
 		return handle_invalid_guest_state(vcpu);
 
+	/*
+	 * the KVM_REQ_EVENT optimization bit is only on for one entry, and if
+	 * we did not inject a still-pending event to L1 now because of
+	 * nested_run_pending, we need to re-enable this bit.
+	 */
+	if (vmx->nested.nested_run_pending)
+		kvm_make_request(KVM_REQ_EVENT, vcpu);
+
+	if (!is_guest_mode(vcpu) && (exit_reason == EXIT_REASON_VMLAUNCH ||
+	    exit_reason == EXIT_REASON_VMRESUME))
+		vmx->nested.nested_run_pending = 1;
+	else
+		vmx->nested.nested_run_pending = 0;
+
+	if (is_guest_mode(vcpu) && nested_vmx_exit_handled(vcpu)) {
+		nested_vmx_vmexit(vcpu);
+		return 1;
+	}
+
 	if (exit_reason & VMX_EXIT_REASONS_FAILED_VMENTRY) {
 		vcpu->run->exit_reason = KVM_EXIT_FAIL_ENTRY;
 		vcpu->run->fail_entry.hardware_entry_failure_reason
@@ -3955,7 +5743,9 @@ static int vmx_handle_exit(struct kvm_vcpu *vcpu)
 		       "(0x%x) and exit reason is 0x%x\n",
 		       __func__, vectoring_info, exit_reason);
 
-	if (unlikely(!cpu_has_virtual_nmis() && vmx->soft_vnmi_blocked)) {
+	if (unlikely(!cpu_has_virtual_nmis() && vmx->soft_vnmi_blocked &&
+	    !(is_guest_mode(vcpu) && nested_cpu_has_virtual_nmis(
+	                                get_vmcs12(vcpu), vcpu)))) {
 		if (vmx_interrupt_allowed(vcpu)) {
 			vmx->soft_vnmi_blocked = 0;
 		} else if (vmx->vnmi_blocked_time > 1000000000LL &&
@@ -4118,6 +5908,8 @@ static void __vmx_complete_interrupts(struct vcpu_vmx *vmx,
 
 static void vmx_complete_interrupts(struct vcpu_vmx *vmx)
 {
+	if (is_guest_mode(&vmx->vcpu))
+		return;
 	__vmx_complete_interrupts(vmx, vmx->idt_vectoring_info,
 				  VM_EXIT_INSTRUCTION_LEN,
 				  IDT_VECTORING_ERROR_CODE);
@@ -4125,6 +5917,8 @@ static void vmx_complete_interrupts(struct vcpu_vmx *vmx)
 
 static void vmx_cancel_injection(struct kvm_vcpu *vcpu)
 {
+	if (is_guest_mode(vcpu))
+		return;
 	__vmx_complete_interrupts(to_vmx(vcpu),
 				  vmcs_read32(VM_ENTRY_INTR_INFO_FIELD),
 				  VM_ENTRY_INSTRUCTION_LEN,
@@ -4145,6 +5939,21 @@ static void __noclone vmx_vcpu_run(struct kvm_vcpu *vcpu)
 {
 	struct vcpu_vmx *vmx = to_vmx(vcpu);
 
+	if (is_guest_mode(vcpu) && !vmx->nested.nested_run_pending) {
+		struct vmcs12 *vmcs12 = get_vmcs12(vcpu);
+		if (vmcs12->idt_vectoring_info_field &
+				VECTORING_INFO_VALID_MASK) {
+			vmcs_write32(VM_ENTRY_INTR_INFO_FIELD,
+				vmcs12->idt_vectoring_info_field);
+			vmcs_write32(VM_ENTRY_INSTRUCTION_LEN,
+				vmcs12->vm_exit_instruction_len);
+			if (vmcs12->idt_vectoring_info_field &
+					VECTORING_INFO_DELIVER_CODE_MASK)
+				vmcs_write32(VM_ENTRY_EXCEPTION_ERROR_CODE,
+					vmcs12->idt_vectoring_error_code);
+		}
+	}
+
 	/* Record the guest's net vcpu time for enforced NMI injections. */
 	if (unlikely(!cpu_has_virtual_nmis() && vmx->soft_vnmi_blocked))
 		vmx->entry_time = ktime_get();
@@ -4167,6 +5976,7 @@ static void __noclone vmx_vcpu_run(struct kvm_vcpu *vcpu)
 	if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP)
 		vmx_set_interrupt_shadow(vcpu, 0);
 
+	vmx->__launched = vmx->loaded_vmcs->launched;
 	asm(
 		/* Store host registers */
 		"push %%"R"dx; push %%"R"bp;"
@@ -4237,7 +6047,7 @@ static void __noclone vmx_vcpu_run(struct kvm_vcpu *vcpu)
 		"pop  %%"R"bp; pop  %%"R"dx \n\t"
 		"setbe %c[fail](%0) \n\t"
 	      : : "c"(vmx), "d"((unsigned long)HOST_RSP),
-		[launched]"i"(offsetof(struct vcpu_vmx, launched)),
+		[launched]"i"(offsetof(struct vcpu_vmx, __launched)),
 		[fail]"i"(offsetof(struct vcpu_vmx, fail)),
 		[host_rsp]"i"(offsetof(struct vcpu_vmx, host_rsp)),
 		[rax]"i"(offsetof(struct vcpu_vmx, vcpu.arch.regs[VCPU_REGS_RAX])),
@@ -4276,8 +6086,19 @@ static void __noclone vmx_vcpu_run(struct kvm_vcpu *vcpu)
 
 	vmx->idt_vectoring_info = vmcs_read32(IDT_VECTORING_INFO_FIELD);
 
+	if (is_guest_mode(vcpu)) {
+		struct vmcs12 *vmcs12 = get_vmcs12(vcpu);
+		vmcs12->idt_vectoring_info_field = vmx->idt_vectoring_info;
+		if (vmx->idt_vectoring_info & VECTORING_INFO_VALID_MASK) {
+			vmcs12->idt_vectoring_error_code =
+				vmcs_read32(IDT_VECTORING_ERROR_CODE);
+			vmcs12->vm_exit_instruction_len =
+				vmcs_read32(VM_EXIT_INSTRUCTION_LEN);
+		}
+	}
+
 	asm("mov %0, %%ds; mov %0, %%es" : : "r"(__USER_DS));
-	vmx->launched = 1;
+	vmx->loaded_vmcs->launched = 1;
 
 	vmx->exit_reason = vmcs_read32(VM_EXIT_REASON);
 
@@ -4289,41 +6110,18 @@ static void __noclone vmx_vcpu_run(struct kvm_vcpu *vcpu)
 #undef R
 #undef Q
 
-static void vmx_free_vmcs(struct kvm_vcpu *vcpu)
-{
-	struct vcpu_vmx *vmx = to_vmx(vcpu);
-
-	if (vmx->vmcs) {
-		vcpu_clear(vmx);
-		free_vmcs(vmx->vmcs);
-		vmx->vmcs = NULL;
-	}
-}
-
 static void vmx_free_vcpu(struct kvm_vcpu *vcpu)
 {
 	struct vcpu_vmx *vmx = to_vmx(vcpu);
 
 	free_vpid(vmx);
-	vmx_free_vmcs(vcpu);
+	free_nested(vmx);
+	free_loaded_vmcs(vmx->loaded_vmcs);
 	kfree(vmx->guest_msrs);
 	kvm_vcpu_uninit(vcpu);
 	kmem_cache_free(kvm_vcpu_cache, vmx);
 }
 
-static inline void vmcs_init(struct vmcs *vmcs)
-{
-	u64 phys_addr = __pa(per_cpu(vmxarea, raw_smp_processor_id()));
-
-	if (!vmm_exclusive)
-		kvm_cpu_vmxon(phys_addr);
-
-	vmcs_clear(vmcs);
-
-	if (!vmm_exclusive)
-		kvm_cpu_vmxoff();
-}
-
 static struct kvm_vcpu *vmx_create_vcpu(struct kvm *kvm, unsigned int id)
 {
 	int err;
@@ -4345,11 +6143,15 @@ static struct kvm_vcpu *vmx_create_vcpu(struct kvm *kvm, unsigned int id)
 		goto uninit_vcpu;
 	}
 
-	vmx->vmcs = alloc_vmcs();
-	if (!vmx->vmcs)
+	vmx->loaded_vmcs = &vmx->vmcs01;
+	vmx->loaded_vmcs->vmcs = alloc_vmcs();
+	if (!vmx->loaded_vmcs->vmcs)
 		goto free_msrs;
-
-	vmcs_init(vmx->vmcs);
+	if (!vmm_exclusive)
+		kvm_cpu_vmxon(__pa(per_cpu(vmxarea, raw_smp_processor_id())));
+	loaded_vmcs_init(vmx->loaded_vmcs);
+	if (!vmm_exclusive)
+		kvm_cpu_vmxoff();
 
 	cpu = get_cpu();
 	vmx_vcpu_load(&vmx->vcpu, cpu);
@@ -4375,10 +6177,13 @@ static struct kvm_vcpu *vmx_create_vcpu(struct kvm *kvm, unsigned int id)
 			goto free_vmcs;
 	}
 
+	vmx->nested.current_vmptr = -1ull;
+	vmx->nested.current_vmcs12 = NULL;
+
 	return &vmx->vcpu;
 
 free_vmcs:
-	free_vmcs(vmx->vmcs);
+	free_vmcs(vmx->loaded_vmcs->vmcs);
 free_msrs:
 	kfree(vmx->guest_msrs);
 uninit_vcpu:
@@ -4512,6 +6317,650 @@ static void vmx_cpuid_update(struct kvm_vcpu *vcpu)
 
 static void vmx_set_supported_cpuid(u32 func, struct kvm_cpuid_entry2 *entry)
 {
+	if (func == 1 && nested)
+		entry->ecx |= bit(X86_FEATURE_VMX);
+}
+
+/*
+ * prepare_vmcs02 is called when the L1 guest hypervisor runs its nested
+ * L2 guest. L1 has a vmcs for L2 (vmcs12), and this function "merges" it
+ * with L0's requirements for its guest (a.k.a. vmsc01), so we can run the L2
+ * guest in a way that will both be appropriate to L1's requests, and our
+ * needs. In addition to modifying the active vmcs (which is vmcs02), this
+ * function also has additional necessary side-effects, like setting various
+ * vcpu->arch fields.
+ */
+static void prepare_vmcs02(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12)
+{
+	struct vcpu_vmx *vmx = to_vmx(vcpu);
+	u32 exec_control;
+
+	vmcs_write16(GUEST_ES_SELECTOR, vmcs12->guest_es_selector);
+	vmcs_write16(GUEST_CS_SELECTOR, vmcs12->guest_cs_selector);
+	vmcs_write16(GUEST_SS_SELECTOR, vmcs12->guest_ss_selector);
+	vmcs_write16(GUEST_DS_SELECTOR, vmcs12->guest_ds_selector);
+	vmcs_write16(GUEST_FS_SELECTOR, vmcs12->guest_fs_selector);
+	vmcs_write16(GUEST_GS_SELECTOR, vmcs12->guest_gs_selector);
+	vmcs_write16(GUEST_LDTR_SELECTOR, vmcs12->guest_ldtr_selector);
+	vmcs_write16(GUEST_TR_SELECTOR, vmcs12->guest_tr_selector);
+	vmcs_write32(GUEST_ES_LIMIT, vmcs12->guest_es_limit);
+	vmcs_write32(GUEST_CS_LIMIT, vmcs12->guest_cs_limit);
+	vmcs_write32(GUEST_SS_LIMIT, vmcs12->guest_ss_limit);
+	vmcs_write32(GUEST_DS_LIMIT, vmcs12->guest_ds_limit);
+	vmcs_write32(GUEST_FS_LIMIT, vmcs12->guest_fs_limit);
+	vmcs_write32(GUEST_GS_LIMIT, vmcs12->guest_gs_limit);
+	vmcs_write32(GUEST_LDTR_LIMIT, vmcs12->guest_ldtr_limit);
+	vmcs_write32(GUEST_TR_LIMIT, vmcs12->guest_tr_limit);
+	vmcs_write32(GUEST_GDTR_LIMIT, vmcs12->guest_gdtr_limit);
+	vmcs_write32(GUEST_IDTR_LIMIT, vmcs12->guest_idtr_limit);
+	vmcs_write32(GUEST_ES_AR_BYTES, vmcs12->guest_es_ar_bytes);
+	vmcs_write32(GUEST_CS_AR_BYTES, vmcs12->guest_cs_ar_bytes);
+	vmcs_write32(GUEST_SS_AR_BYTES, vmcs12->guest_ss_ar_bytes);
+	vmcs_write32(GUEST_DS_AR_BYTES, vmcs12->guest_ds_ar_bytes);
+	vmcs_write32(GUEST_FS_AR_BYTES, vmcs12->guest_fs_ar_bytes);
+	vmcs_write32(GUEST_GS_AR_BYTES, vmcs12->guest_gs_ar_bytes);
+	vmcs_write32(GUEST_LDTR_AR_BYTES, vmcs12->guest_ldtr_ar_bytes);
+	vmcs_write32(GUEST_TR_AR_BYTES, vmcs12->guest_tr_ar_bytes);
+	vmcs_writel(GUEST_ES_BASE, vmcs12->guest_es_base);
+	vmcs_writel(GUEST_CS_BASE, vmcs12->guest_cs_base);
+	vmcs_writel(GUEST_SS_BASE, vmcs12->guest_ss_base);
+	vmcs_writel(GUEST_DS_BASE, vmcs12->guest_ds_base);
+	vmcs_writel(GUEST_FS_BASE, vmcs12->guest_fs_base);
+	vmcs_writel(GUEST_GS_BASE, vmcs12->guest_gs_base);
+	vmcs_writel(GUEST_LDTR_BASE, vmcs12->guest_ldtr_base);
+	vmcs_writel(GUEST_TR_BASE, vmcs12->guest_tr_base);
+	vmcs_writel(GUEST_GDTR_BASE, vmcs12->guest_gdtr_base);
+	vmcs_writel(GUEST_IDTR_BASE, vmcs12->guest_idtr_base);
+
+	vmcs_write64(GUEST_IA32_DEBUGCTL, vmcs12->guest_ia32_debugctl);
+	vmcs_write32(VM_ENTRY_INTR_INFO_FIELD,
+		vmcs12->vm_entry_intr_info_field);
+	vmcs_write32(VM_ENTRY_EXCEPTION_ERROR_CODE,
+		vmcs12->vm_entry_exception_error_code);
+	vmcs_write32(VM_ENTRY_INSTRUCTION_LEN,
+		vmcs12->vm_entry_instruction_len);
+	vmcs_write32(GUEST_INTERRUPTIBILITY_INFO,
+		vmcs12->guest_interruptibility_info);
+	vmcs_write32(GUEST_ACTIVITY_STATE, vmcs12->guest_activity_state);
+	vmcs_write32(GUEST_SYSENTER_CS, vmcs12->guest_sysenter_cs);
+	vmcs_writel(GUEST_DR7, vmcs12->guest_dr7);
+	vmcs_writel(GUEST_RFLAGS, vmcs12->guest_rflags);
+	vmcs_writel(GUEST_PENDING_DBG_EXCEPTIONS,
+		vmcs12->guest_pending_dbg_exceptions);
+	vmcs_writel(GUEST_SYSENTER_ESP, vmcs12->guest_sysenter_esp);
+	vmcs_writel(GUEST_SYSENTER_EIP, vmcs12->guest_sysenter_eip);
+
+	vmcs_write64(VMCS_LINK_POINTER, -1ull);
+
+	vmcs_write32(PIN_BASED_VM_EXEC_CONTROL,
+		(vmcs_config.pin_based_exec_ctrl |
+		 vmcs12->pin_based_vm_exec_control));
+
+	/*
+	 * Whether page-faults are trapped is determined by a combination of
+	 * 3 settings: PFEC_MASK, PFEC_MATCH and EXCEPTION_BITMAP.PF.
+	 * If enable_ept, L0 doesn't care about page faults and we should
+	 * set all of these to L1's desires. However, if !enable_ept, L0 does
+	 * care about (at least some) page faults, and because it is not easy
+	 * (if at all possible?) to merge L0 and L1's desires, we simply ask
+	 * to exit on each and every L2 page fault. This is done by setting
+	 * MASK=MATCH=0 and (see below) EB.PF=1.
+	 * Note that below we don't need special code to set EB.PF beyond the
+	 * "or"ing of the EB of vmcs01 and vmcs12, because when enable_ept,
+	 * vmcs01's EB.PF is 0 so the "or" will take vmcs12's value, and when
+	 * !enable_ept, EB.PF is 1, so the "or" will always be 1.
+	 *
+	 * A problem with this approach (when !enable_ept) is that L1 may be
+	 * injected with more page faults than it asked for. This could have
+	 * caused problems, but in practice existing hypervisors don't care.
+	 * To fix this, we will need to emulate the PFEC checking (on the L1
+	 * page tables), using walk_addr(), when injecting PFs to L1.
+	 */
+	vmcs_write32(PAGE_FAULT_ERROR_CODE_MASK,
+		enable_ept ? vmcs12->page_fault_error_code_mask : 0);
+	vmcs_write32(PAGE_FAULT_ERROR_CODE_MATCH,
+		enable_ept ? vmcs12->page_fault_error_code_match : 0);
+
+	if (cpu_has_secondary_exec_ctrls()) {
+		u32 exec_control = vmx_secondary_exec_control(vmx);
+		if (!vmx->rdtscp_enabled)
+			exec_control &= ~SECONDARY_EXEC_RDTSCP;
+		/* Take the following fields only from vmcs12 */
+		exec_control &= ~SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES;
+		if (nested_cpu_has(vmcs12,
+				CPU_BASED_ACTIVATE_SECONDARY_CONTROLS))
+			exec_control |= vmcs12->secondary_vm_exec_control;
+
+		if (exec_control & SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES) {
+			/*
+			 * Translate L1 physical address to host physical
+			 * address for vmcs02. Keep the page pinned, so this
+			 * physical address remains valid. We keep a reference
+			 * to it so we can release it later.
+			 */
+			if (vmx->nested.apic_access_page) /* shouldn't happen */
+				nested_release_page(vmx->nested.apic_access_page);
+			vmx->nested.apic_access_page =
+				nested_get_page(vcpu, vmcs12->apic_access_addr);
+			/*
+			 * If translation failed, no matter: This feature asks
+			 * to exit when accessing the given address, and if it
+			 * can never be accessed, this feature won't do
+			 * anything anyway.
+			 */
+			if (!vmx->nested.apic_access_page)
+				exec_control &=
+				  ~SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES;
+			else
+				vmcs_write64(APIC_ACCESS_ADDR,
+				  page_to_phys(vmx->nested.apic_access_page));
+		}
+
+		vmcs_write32(SECONDARY_VM_EXEC_CONTROL, exec_control);
+	}
+
+
+	/*
+	 * Set host-state according to L0's settings (vmcs12 is irrelevant here)
+	 * Some constant fields are set here by vmx_set_constant_host_state().
+	 * Other fields are different per CPU, and will be set later when
+	 * vmx_vcpu_load() is called, and when vmx_save_host_state() is called.
+	 */
+	vmx_set_constant_host_state();
+
+	/*
+	 * HOST_RSP is normally set correctly in vmx_vcpu_run() just before
+	 * entry, but only if the current (host) sp changed from the value
+	 * we wrote last (vmx->host_rsp). This cache is no longer relevant
+	 * if we switch vmcs, and rather than hold a separate cache per vmcs,
+	 * here we just force the write to happen on entry.
+	 */
+	vmx->host_rsp = 0;
+
+	exec_control = vmx_exec_control(vmx); /* L0's desires */
+	exec_control &= ~CPU_BASED_VIRTUAL_INTR_PENDING;
+	exec_control &= ~CPU_BASED_VIRTUAL_NMI_PENDING;
+	exec_control &= ~CPU_BASED_TPR_SHADOW;
+	exec_control |= vmcs12->cpu_based_vm_exec_control;
+	/*
+	 * Merging of IO and MSR bitmaps not currently supported.
+	 * Rather, exit every time.
+	 */
+	exec_control &= ~CPU_BASED_USE_MSR_BITMAPS;
+	exec_control &= ~CPU_BASED_USE_IO_BITMAPS;
+	exec_control |= CPU_BASED_UNCOND_IO_EXITING;
+
+	vmcs_write32(CPU_BASED_VM_EXEC_CONTROL, exec_control);
+
+	/* EXCEPTION_BITMAP and CR0_GUEST_HOST_MASK should basically be the
+	 * bitwise-or of what L1 wants to trap for L2, and what we want to
+	 * trap. Note that CR0.TS also needs updating - we do this later.
+	 */
+	update_exception_bitmap(vcpu);
+	vcpu->arch.cr0_guest_owned_bits &= ~vmcs12->cr0_guest_host_mask;
+	vmcs_writel(CR0_GUEST_HOST_MASK, ~vcpu->arch.cr0_guest_owned_bits);
+
+	/* Note: IA32_MODE, LOAD_IA32_EFER are modified by vmx_set_efer below */
+	vmcs_write32(VM_EXIT_CONTROLS,
+		vmcs12->vm_exit_controls | vmcs_config.vmexit_ctrl);
+	vmcs_write32(VM_ENTRY_CONTROLS, vmcs12->vm_entry_controls |
+		(vmcs_config.vmentry_ctrl & ~VM_ENTRY_IA32E_MODE));
+
+	if (vmcs12->vm_entry_controls & VM_ENTRY_LOAD_IA32_PAT)
+		vmcs_write64(GUEST_IA32_PAT, vmcs12->guest_ia32_pat);
+	else if (vmcs_config.vmentry_ctrl & VM_ENTRY_LOAD_IA32_PAT)
+		vmcs_write64(GUEST_IA32_PAT, vmx->vcpu.arch.pat);
+
+
+	set_cr4_guest_host_mask(vmx);
+
+	vmcs_write64(TSC_OFFSET,
+		vmx->nested.vmcs01_tsc_offset + vmcs12->tsc_offset);
+
+	if (enable_vpid) {
+		/*
+		 * Trivially support vpid by letting L2s share their parent
+		 * L1's vpid. TODO: move to a more elaborate solution, giving
+		 * each L2 its own vpid and exposing the vpid feature to L1.
+		 */
+		vmcs_write16(VIRTUAL_PROCESSOR_ID, vmx->vpid);
+		vmx_flush_tlb(vcpu);
+	}
+
+	if (vmcs12->vm_entry_controls & VM_ENTRY_LOAD_IA32_EFER)
+		vcpu->arch.efer = vmcs12->guest_ia32_efer;
+	if (vmcs12->vm_entry_controls & VM_ENTRY_IA32E_MODE)
+		vcpu->arch.efer |= (EFER_LMA | EFER_LME);
+	else
+		vcpu->arch.efer &= ~(EFER_LMA | EFER_LME);
+	/* Note: modifies VM_ENTRY/EXIT_CONTROLS and GUEST/HOST_IA32_EFER */
+	vmx_set_efer(vcpu, vcpu->arch.efer);
+
+	/*
+	 * This sets GUEST_CR0 to vmcs12->guest_cr0, with possibly a modified
+	 * TS bit (for lazy fpu) and bits which we consider mandatory enabled.
+	 * The CR0_READ_SHADOW is what L2 should have expected to read given
+	 * the specifications by L1; It's not enough to take
+	 * vmcs12->cr0_read_shadow because on our cr0_guest_host_mask we we
+	 * have more bits than L1 expected.
+	 */
+	vmx_set_cr0(vcpu, vmcs12->guest_cr0);
+	vmcs_writel(CR0_READ_SHADOW, nested_read_cr0(vmcs12));
+
+	vmx_set_cr4(vcpu, vmcs12->guest_cr4);
+	vmcs_writel(CR4_READ_SHADOW, nested_read_cr4(vmcs12));
+
+	/* shadow page tables on either EPT or shadow page tables */
+	kvm_set_cr3(vcpu, vmcs12->guest_cr3);
+	kvm_mmu_reset_context(vcpu);
+
+	kvm_register_write(vcpu, VCPU_REGS_RSP, vmcs12->guest_rsp);
+	kvm_register_write(vcpu, VCPU_REGS_RIP, vmcs12->guest_rip);
+}
+
+/*
+ * nested_vmx_run() handles a nested entry, i.e., a VMLAUNCH or VMRESUME on L1
+ * for running an L2 nested guest.
+ */
+static int nested_vmx_run(struct kvm_vcpu *vcpu, bool launch)
+{
+	struct vmcs12 *vmcs12;
+	struct vcpu_vmx *vmx = to_vmx(vcpu);
+	int cpu;
+	struct loaded_vmcs *vmcs02;
+
+	if (!nested_vmx_check_permission(vcpu) ||
+	    !nested_vmx_check_vmcs12(vcpu))
+		return 1;
+
+	skip_emulated_instruction(vcpu);
+	vmcs12 = get_vmcs12(vcpu);
+
+	/*
+	 * The nested entry process starts with enforcing various prerequisites
+	 * on vmcs12 as required by the Intel SDM, and act appropriately when
+	 * they fail: As the SDM explains, some conditions should cause the
+	 * instruction to fail, while others will cause the instruction to seem
+	 * to succeed, but return an EXIT_REASON_INVALID_STATE.
+	 * To speed up the normal (success) code path, we should avoid checking
+	 * for misconfigurations which will anyway be caught by the processor
+	 * when using the merged vmcs02.
+	 */
+	if (vmcs12->launch_state == launch) {
+		nested_vmx_failValid(vcpu,
+			launch ? VMXERR_VMLAUNCH_NONCLEAR_VMCS
+			       : VMXERR_VMRESUME_NONLAUNCHED_VMCS);
+		return 1;
+	}
+
+	if ((vmcs12->cpu_based_vm_exec_control & CPU_BASED_USE_MSR_BITMAPS) &&
+			!IS_ALIGNED(vmcs12->msr_bitmap, PAGE_SIZE)) {
+		/*TODO: Also verify bits beyond physical address width are 0*/
+		nested_vmx_failValid(vcpu, VMXERR_ENTRY_INVALID_CONTROL_FIELD);
+		return 1;
+	}
+
+	if (nested_cpu_has2(vmcs12, SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES) &&
+			!IS_ALIGNED(vmcs12->apic_access_addr, PAGE_SIZE)) {
+		/*TODO: Also verify bits beyond physical address width are 0*/
+		nested_vmx_failValid(vcpu, VMXERR_ENTRY_INVALID_CONTROL_FIELD);
+		return 1;
+	}
+
+	if (vmcs12->vm_entry_msr_load_count > 0 ||
+	    vmcs12->vm_exit_msr_load_count > 0 ||
+	    vmcs12->vm_exit_msr_store_count > 0) {
+		if (printk_ratelimit())
+			printk(KERN_WARNING
+			  "%s: VMCS MSR_{LOAD,STORE} unsupported\n", __func__);
+		nested_vmx_failValid(vcpu, VMXERR_ENTRY_INVALID_CONTROL_FIELD);
+		return 1;
+	}
+
+	if (!vmx_control_verify(vmcs12->cpu_based_vm_exec_control,
+	      nested_vmx_procbased_ctls_low, nested_vmx_procbased_ctls_high) ||
+	    !vmx_control_verify(vmcs12->secondary_vm_exec_control,
+	      nested_vmx_secondary_ctls_low, nested_vmx_secondary_ctls_high) ||
+	    !vmx_control_verify(vmcs12->pin_based_vm_exec_control,
+	      nested_vmx_pinbased_ctls_low, nested_vmx_pinbased_ctls_high) ||
+	    !vmx_control_verify(vmcs12->vm_exit_controls,
+	      nested_vmx_exit_ctls_low, nested_vmx_exit_ctls_high) ||
+	    !vmx_control_verify(vmcs12->vm_entry_controls,
+	      nested_vmx_entry_ctls_low, nested_vmx_entry_ctls_high))
+	{
+		nested_vmx_failValid(vcpu, VMXERR_ENTRY_INVALID_CONTROL_FIELD);
+		return 1;
+	}
+
+	if (((vmcs12->host_cr0 & VMXON_CR0_ALWAYSON) != VMXON_CR0_ALWAYSON) ||
+	    ((vmcs12->host_cr4 & VMXON_CR4_ALWAYSON) != VMXON_CR4_ALWAYSON)) {
+		nested_vmx_failValid(vcpu,
+			VMXERR_ENTRY_INVALID_HOST_STATE_FIELD);
+		return 1;
+	}
+
+	if (((vmcs12->guest_cr0 & VMXON_CR0_ALWAYSON) != VMXON_CR0_ALWAYSON) ||
+	    ((vmcs12->guest_cr4 & VMXON_CR4_ALWAYSON) != VMXON_CR4_ALWAYSON)) {
+		nested_vmx_entry_failure(vcpu, vmcs12,
+			EXIT_REASON_INVALID_STATE, ENTRY_FAIL_DEFAULT);
+		return 1;
+	}
+	if (vmcs12->vmcs_link_pointer != -1ull) {
+		nested_vmx_entry_failure(vcpu, vmcs12,
+			EXIT_REASON_INVALID_STATE, ENTRY_FAIL_VMCS_LINK_PTR);
+		return 1;
+	}
+
+	/*
+	 * We're finally done with prerequisite checking, and can start with
+	 * the nested entry.
+	 */
+
+	vmcs02 = nested_get_current_vmcs02(vmx);
+	if (!vmcs02)
+		return -ENOMEM;
+
+	enter_guest_mode(vcpu);
+
+	vmx->nested.vmcs01_tsc_offset = vmcs_read64(TSC_OFFSET);
+
+	cpu = get_cpu();
+	vmx->loaded_vmcs = vmcs02;
+	vmx_vcpu_put(vcpu);
+	vmx_vcpu_load(vcpu, cpu);
+	vcpu->cpu = cpu;
+	put_cpu();
+
+	vmcs12->launch_state = 1;
+
+	prepare_vmcs02(vcpu, vmcs12);
+
+	/*
+	 * Note no nested_vmx_succeed or nested_vmx_fail here. At this point
+	 * we are no longer running L1, and VMLAUNCH/VMRESUME has not yet
+	 * returned as far as L1 is concerned. It will only return (and set
+	 * the success flag) when L2 exits (see nested_vmx_vmexit()).
+	 */
+	return 1;
+}
+
+/*
+ * On a nested exit from L2 to L1, vmcs12.guest_cr0 might not be up-to-date
+ * because L2 may have changed some cr0 bits directly (CRO_GUEST_HOST_MASK).
+ * This function returns the new value we should put in vmcs12.guest_cr0.
+ * It's not enough to just return the vmcs02 GUEST_CR0. Rather,
+ *  1. Bits that neither L0 nor L1 trapped, were set directly by L2 and are now
+ *     available in vmcs02 GUEST_CR0. (Note: It's enough to check that L0
+ *     didn't trap the bit, because if L1 did, so would L0).
+ *  2. Bits that L1 asked to trap (and therefore L0 also did) could not have
+ *     been modified by L2, and L1 knows it. So just leave the old value of
+ *     the bit from vmcs12.guest_cr0. Note that the bit from vmcs02 GUEST_CR0
+ *     isn't relevant, because if L0 traps this bit it can set it to anything.
+ *  3. Bits that L1 didn't trap, but L0 did. L1 believes the guest could have
+ *     changed these bits, and therefore they need to be updated, but L0
+ *     didn't necessarily allow them to be changed in GUEST_CR0 - and rather
+ *     put them in vmcs02 CR0_READ_SHADOW. So take these bits from there.
+ */
+static inline unsigned long
+vmcs12_guest_cr0(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12)
+{
+	return
+	/*1*/	(vmcs_readl(GUEST_CR0) & vcpu->arch.cr0_guest_owned_bits) |
+	/*2*/	(vmcs12->guest_cr0 & vmcs12->cr0_guest_host_mask) |
+	/*3*/	(vmcs_readl(CR0_READ_SHADOW) & ~(vmcs12->cr0_guest_host_mask |
+			vcpu->arch.cr0_guest_owned_bits));
+}
+
+static inline unsigned long
+vmcs12_guest_cr4(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12)
+{
+	return
+	/*1*/	(vmcs_readl(GUEST_CR4) & vcpu->arch.cr4_guest_owned_bits) |
+	/*2*/	(vmcs12->guest_cr4 & vmcs12->cr4_guest_host_mask) |
+	/*3*/	(vmcs_readl(CR4_READ_SHADOW) & ~(vmcs12->cr4_guest_host_mask |
+			vcpu->arch.cr4_guest_owned_bits));
+}
+
+/*
+ * prepare_vmcs12 is part of what we need to do when the nested L2 guest exits
+ * and we want to prepare to run its L1 parent. L1 keeps a vmcs for L2 (vmcs12),
+ * and this function updates it to reflect the changes to the guest state while
+ * L2 was running (and perhaps made some exits which were handled directly by L0
+ * without going back to L1), and to reflect the exit reason.
+ * Note that we do not have to copy here all VMCS fields, just those that
+ * could have changed by the L2 guest or the exit - i.e., the guest-state and
+ * exit-information fields only. Other fields are modified by L1 with VMWRITE,
+ * which already writes to vmcs12 directly.
+ */
+void prepare_vmcs12(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12)
+{
+	/* update guest state fields: */
+	vmcs12->guest_cr0 = vmcs12_guest_cr0(vcpu, vmcs12);
+	vmcs12->guest_cr4 = vmcs12_guest_cr4(vcpu, vmcs12);
+
+	kvm_get_dr(vcpu, 7, (unsigned long *)&vmcs12->guest_dr7);
+	vmcs12->guest_rsp = kvm_register_read(vcpu, VCPU_REGS_RSP);
+	vmcs12->guest_rip = kvm_register_read(vcpu, VCPU_REGS_RIP);
+	vmcs12->guest_rflags = vmcs_readl(GUEST_RFLAGS);
+
+	vmcs12->guest_es_selector = vmcs_read16(GUEST_ES_SELECTOR);
+	vmcs12->guest_cs_selector = vmcs_read16(GUEST_CS_SELECTOR);
+	vmcs12->guest_ss_selector = vmcs_read16(GUEST_SS_SELECTOR);
+	vmcs12->guest_ds_selector = vmcs_read16(GUEST_DS_SELECTOR);
+	vmcs12->guest_fs_selector = vmcs_read16(GUEST_FS_SELECTOR);
+	vmcs12->guest_gs_selector = vmcs_read16(GUEST_GS_SELECTOR);
+	vmcs12->guest_ldtr_selector = vmcs_read16(GUEST_LDTR_SELECTOR);
+	vmcs12->guest_tr_selector = vmcs_read16(GUEST_TR_SELECTOR);
+	vmcs12->guest_es_limit = vmcs_read32(GUEST_ES_LIMIT);
+	vmcs12->guest_cs_limit = vmcs_read32(GUEST_CS_LIMIT);
+	vmcs12->guest_ss_limit = vmcs_read32(GUEST_SS_LIMIT);
+	vmcs12->guest_ds_limit = vmcs_read32(GUEST_DS_LIMIT);
+	vmcs12->guest_fs_limit = vmcs_read32(GUEST_FS_LIMIT);
+	vmcs12->guest_gs_limit = vmcs_read32(GUEST_GS_LIMIT);
+	vmcs12->guest_ldtr_limit = vmcs_read32(GUEST_LDTR_LIMIT);
+	vmcs12->guest_tr_limit = vmcs_read32(GUEST_TR_LIMIT);
+	vmcs12->guest_gdtr_limit = vmcs_read32(GUEST_GDTR_LIMIT);
+	vmcs12->guest_idtr_limit = vmcs_read32(GUEST_IDTR_LIMIT);
+	vmcs12->guest_es_ar_bytes = vmcs_read32(GUEST_ES_AR_BYTES);
+	vmcs12->guest_cs_ar_bytes = vmcs_read32(GUEST_CS_AR_BYTES);
+	vmcs12->guest_ss_ar_bytes = vmcs_read32(GUEST_SS_AR_BYTES);
+	vmcs12->guest_ds_ar_bytes = vmcs_read32(GUEST_DS_AR_BYTES);
+	vmcs12->guest_fs_ar_bytes = vmcs_read32(GUEST_FS_AR_BYTES);
+	vmcs12->guest_gs_ar_bytes = vmcs_read32(GUEST_GS_AR_BYTES);
+	vmcs12->guest_ldtr_ar_bytes = vmcs_read32(GUEST_LDTR_AR_BYTES);
+	vmcs12->guest_tr_ar_bytes = vmcs_read32(GUEST_TR_AR_BYTES);
+	vmcs12->guest_es_base = vmcs_readl(GUEST_ES_BASE);
+	vmcs12->guest_cs_base = vmcs_readl(GUEST_CS_BASE);
+	vmcs12->guest_ss_base = vmcs_readl(GUEST_SS_BASE);
+	vmcs12->guest_ds_base = vmcs_readl(GUEST_DS_BASE);
+	vmcs12->guest_fs_base = vmcs_readl(GUEST_FS_BASE);
+	vmcs12->guest_gs_base = vmcs_readl(GUEST_GS_BASE);
+	vmcs12->guest_ldtr_base = vmcs_readl(GUEST_LDTR_BASE);
+	vmcs12->guest_tr_base = vmcs_readl(GUEST_TR_BASE);
+	vmcs12->guest_gdtr_base = vmcs_readl(GUEST_GDTR_BASE);
+	vmcs12->guest_idtr_base = vmcs_readl(GUEST_IDTR_BASE);
+
+	vmcs12->guest_activity_state = vmcs_read32(GUEST_ACTIVITY_STATE);
+	vmcs12->guest_interruptibility_info =
+		vmcs_read32(GUEST_INTERRUPTIBILITY_INFO);
+	vmcs12->guest_pending_dbg_exceptions =
+		vmcs_readl(GUEST_PENDING_DBG_EXCEPTIONS);
+
+	/* TODO: These cannot have changed unless we have MSR bitmaps and
+	 * the relevant bit asks not to trap the change */
+	vmcs12->guest_ia32_debugctl = vmcs_read64(GUEST_IA32_DEBUGCTL);
+	if (vmcs12->vm_entry_controls & VM_EXIT_SAVE_IA32_PAT)
+		vmcs12->guest_ia32_pat = vmcs_read64(GUEST_IA32_PAT);
+	vmcs12->guest_sysenter_cs = vmcs_read32(GUEST_SYSENTER_CS);
+	vmcs12->guest_sysenter_esp = vmcs_readl(GUEST_SYSENTER_ESP);
+	vmcs12->guest_sysenter_eip = vmcs_readl(GUEST_SYSENTER_EIP);
+
+	/* update exit information fields: */
+
+	vmcs12->vm_exit_reason  = vmcs_read32(VM_EXIT_REASON);
+	vmcs12->exit_qualification = vmcs_readl(EXIT_QUALIFICATION);
+
+	vmcs12->vm_exit_intr_info = vmcs_read32(VM_EXIT_INTR_INFO);
+	vmcs12->vm_exit_intr_error_code = vmcs_read32(VM_EXIT_INTR_ERROR_CODE);
+	vmcs12->idt_vectoring_info_field =
+		vmcs_read32(IDT_VECTORING_INFO_FIELD);
+	vmcs12->idt_vectoring_error_code =
+		vmcs_read32(IDT_VECTORING_ERROR_CODE);
+	vmcs12->vm_exit_instruction_len = vmcs_read32(VM_EXIT_INSTRUCTION_LEN);
+	vmcs12->vmx_instruction_info = vmcs_read32(VMX_INSTRUCTION_INFO);
+
+	/* clear vm-entry fields which are to be cleared on exit */
+	if (!(vmcs12->vm_exit_reason & VMX_EXIT_REASONS_FAILED_VMENTRY))
+		vmcs12->vm_entry_intr_info_field &= ~INTR_INFO_VALID_MASK;
+}
+
+/*
+ * A part of what we need to when the nested L2 guest exits and we want to
+ * run its L1 parent, is to reset L1's guest state to the host state specified
+ * in vmcs12.
+ * This function is to be called not only on normal nested exit, but also on
+ * a nested entry failure, as explained in Intel's spec, 3B.23.7 ("VM-Entry
+ * Failures During or After Loading Guest State").
+ * This function should be called when the active VMCS is L1's (vmcs01).
+ */
+void load_vmcs12_host_state(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12)
+{
+	if (vmcs12->vm_exit_controls & VM_EXIT_LOAD_IA32_EFER)
+		vcpu->arch.efer = vmcs12->host_ia32_efer;
+	if (vmcs12->vm_exit_controls & VM_EXIT_HOST_ADDR_SPACE_SIZE)
+		vcpu->arch.efer |= (EFER_LMA | EFER_LME);
+	else
+		vcpu->arch.efer &= ~(EFER_LMA | EFER_LME);
+	vmx_set_efer(vcpu, vcpu->arch.efer);
+
+	kvm_register_write(vcpu, VCPU_REGS_RSP, vmcs12->host_rsp);
+	kvm_register_write(vcpu, VCPU_REGS_RIP, vmcs12->host_rip);
+	/*
+	 * Note that calling vmx_set_cr0 is important, even if cr0 hasn't
+	 * actually changed, because it depends on the current state of
+	 * fpu_active (which may have changed).
+	 * Note that vmx_set_cr0 refers to efer set above.
+	 */
+	kvm_set_cr0(vcpu, vmcs12->host_cr0);
+	/*
+	 * If we did fpu_activate()/fpu_deactivate() during L2's run, we need
+	 * to apply the same changes to L1's vmcs. We just set cr0 correctly,
+	 * but we also need to update cr0_guest_host_mask and exception_bitmap.
+	 */
+	update_exception_bitmap(vcpu);
+	vcpu->arch.cr0_guest_owned_bits = (vcpu->fpu_active ? X86_CR0_TS : 0);
+	vmcs_writel(CR0_GUEST_HOST_MASK, ~vcpu->arch.cr0_guest_owned_bits);
+
+	/*
+	 * Note that CR4_GUEST_HOST_MASK is already set in the original vmcs01
+	 * (KVM doesn't change it)- no reason to call set_cr4_guest_host_mask();
+	 */
+	vcpu->arch.cr4_guest_owned_bits = ~vmcs_readl(CR4_GUEST_HOST_MASK);
+	kvm_set_cr4(vcpu, vmcs12->host_cr4);
+
+	/* shadow page tables on either EPT or shadow page tables */
+	kvm_set_cr3(vcpu, vmcs12->host_cr3);
+	kvm_mmu_reset_context(vcpu);
+
+	if (enable_vpid) {
+		/*
+		 * Trivially support vpid by letting L2s share their parent
+		 * L1's vpid. TODO: move to a more elaborate solution, giving
+		 * each L2 its own vpid and exposing the vpid feature to L1.
+		 */
+		vmx_flush_tlb(vcpu);
+	}
+
+
+	vmcs_write32(GUEST_SYSENTER_CS, vmcs12->host_ia32_sysenter_cs);
+	vmcs_writel(GUEST_SYSENTER_ESP, vmcs12->host_ia32_sysenter_esp);
+	vmcs_writel(GUEST_SYSENTER_EIP, vmcs12->host_ia32_sysenter_eip);
+	vmcs_writel(GUEST_IDTR_BASE, vmcs12->host_idtr_base);
+	vmcs_writel(GUEST_GDTR_BASE, vmcs12->host_gdtr_base);
+	vmcs_writel(GUEST_TR_BASE, vmcs12->host_tr_base);
+	vmcs_writel(GUEST_GS_BASE, vmcs12->host_gs_base);
+	vmcs_writel(GUEST_FS_BASE, vmcs12->host_fs_base);
+	vmcs_write16(GUEST_ES_SELECTOR, vmcs12->host_es_selector);
+	vmcs_write16(GUEST_CS_SELECTOR, vmcs12->host_cs_selector);
+	vmcs_write16(GUEST_SS_SELECTOR, vmcs12->host_ss_selector);
+	vmcs_write16(GUEST_DS_SELECTOR, vmcs12->host_ds_selector);
+	vmcs_write16(GUEST_FS_SELECTOR, vmcs12->host_fs_selector);
+	vmcs_write16(GUEST_GS_SELECTOR, vmcs12->host_gs_selector);
+	vmcs_write16(GUEST_TR_SELECTOR, vmcs12->host_tr_selector);
+
+	if (vmcs12->vm_exit_controls & VM_EXIT_LOAD_IA32_PAT)
+		vmcs_write64(GUEST_IA32_PAT, vmcs12->host_ia32_pat);
+	if (vmcs12->vm_exit_controls & VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL)
+		vmcs_write64(GUEST_IA32_PERF_GLOBAL_CTRL,
+			vmcs12->host_ia32_perf_global_ctrl);
+}
+
+/*
+ * Emulate an exit from nested guest (L2) to L1, i.e., prepare to run L1
+ * and modify vmcs12 to make it see what it would expect to see there if
+ * L2 was its real guest. Must only be called when in L2 (is_guest_mode())
+ */
+static void nested_vmx_vmexit(struct kvm_vcpu *vcpu)
+{
+	struct vcpu_vmx *vmx = to_vmx(vcpu);
+	int cpu;
+	struct vmcs12 *vmcs12 = get_vmcs12(vcpu);
+
+	leave_guest_mode(vcpu);
+	prepare_vmcs12(vcpu, vmcs12);
+
+	cpu = get_cpu();
+	vmx->loaded_vmcs = &vmx->vmcs01;
+	vmx_vcpu_put(vcpu);
+	vmx_vcpu_load(vcpu, cpu);
+	vcpu->cpu = cpu;
+	put_cpu();
+
+	/* if no vmcs02 cache requested, remove the one we used */
+	if (VMCS02_POOL_SIZE == 0)
+		nested_free_vmcs02(vmx, vmx->nested.current_vmptr);
+
+	load_vmcs12_host_state(vcpu, vmcs12);
+
+	/* Update TSC_OFFSET if vmx_adjust_tsc_offset() was used while L2 ran */
+	vmcs_write64(TSC_OFFSET, vmx->nested.vmcs01_tsc_offset);
+
+	/* This is needed for same reason as it was needed in prepare_vmcs02 */
+	vmx->host_rsp = 0;
+
+	/* Unpin physical memory we referred to in vmcs02 */
+	if (vmx->nested.apic_access_page) {
+		nested_release_page(vmx->nested.apic_access_page);
+		vmx->nested.apic_access_page = 0;
+	}
+
+	/*
+	 * Exiting from L2 to L1, we're now back to L1 which thinks it just
+	 * finished a VMLAUNCH or VMRESUME instruction, so we need to set the
+	 * success or failure flag accordingly.
+	 */
+	if (unlikely(vmx->fail)) {
+		vmx->fail = 0;
+		nested_vmx_failValid(vcpu, vmcs_read32(VM_INSTRUCTION_ERROR));
+	} else
+		nested_vmx_succeed(vcpu);
+}
+
+/*
+ * L1's failure to enter L2 is a subset of a normal exit, as explained in
+ * 23.7 "VM-entry failures during or after loading guest state" (this also
+ * lists the acceptable exit-reason and exit-qualification parameters).
+ * It should only be called before L2 actually succeeded to run, and when
+ * vmcs01 is current (it doesn't leave_guest_mode() or switch vmcss).
+ */
+static void nested_vmx_entry_failure(struct kvm_vcpu *vcpu,
+			struct vmcs12 *vmcs12,
+			u32 reason, unsigned long qualification)
+{
+	load_vmcs12_host_state(vcpu, vmcs12);
+	vmcs12->vm_exit_reason = reason | VMX_EXIT_REASONS_FAILED_VMENTRY;
+	vmcs12->exit_qualification = qualification;
+	nested_vmx_succeed(vcpu);
 }
 
 static int vmx_check_intercept(struct kvm_vcpu *vcpu,
@@ -4670,16 +7119,13 @@ static int __init vmx_init(void)
 	vmx_disable_intercept_for_msr(MSR_IA32_SYSENTER_EIP, false);
 
 	if (enable_ept) {
-		bypass_guest_pf = 0;
 		kvm_mmu_set_mask_ptes(0ull, 0ull, 0ull, 0ull,
 				VMX_EPT_EXECUTABLE_MASK);
+		ept_set_mmio_spte_mask();
 		kvm_enable_tdp();
 	} else
 		kvm_disable_tdp();
 
-	if (bypass_guest_pf)
-		kvm_mmu_set_nonpresent_ptes(~0xffeull, 0ull);
-
 	return 0;
 
 out3:
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 77c9d8673dc4..84a28ea45fa4 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -347,6 +347,7 @@ void kvm_inject_page_fault(struct kvm_vcpu *vcpu, struct x86_exception *fault)
 	vcpu->arch.cr2 = fault->address;
 	kvm_queue_exception_e(vcpu, PF_VECTOR, fault->error_code);
 }
+EXPORT_SYMBOL_GPL(kvm_inject_page_fault);
 
 void kvm_propagate_fault(struct kvm_vcpu *vcpu, struct x86_exception *fault)
 {
@@ -579,6 +580,22 @@ static bool guest_cpuid_has_xsave(struct kvm_vcpu *vcpu)
 	return best && (best->ecx & bit(X86_FEATURE_XSAVE));
 }
 
+static bool guest_cpuid_has_smep(struct kvm_vcpu *vcpu)
+{
+	struct kvm_cpuid_entry2 *best;
+
+	best = kvm_find_cpuid_entry(vcpu, 7, 0);
+	return best && (best->ebx & bit(X86_FEATURE_SMEP));
+}
+
+static bool guest_cpuid_has_fsgsbase(struct kvm_vcpu *vcpu)
+{
+	struct kvm_cpuid_entry2 *best;
+
+	best = kvm_find_cpuid_entry(vcpu, 7, 0);
+	return best && (best->ebx & bit(X86_FEATURE_FSGSBASE));
+}
+
 static void update_cpuid(struct kvm_vcpu *vcpu)
 {
 	struct kvm_cpuid_entry2 *best;
@@ -598,14 +615,20 @@ static void update_cpuid(struct kvm_vcpu *vcpu)
 int kvm_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4)
 {
 	unsigned long old_cr4 = kvm_read_cr4(vcpu);
-	unsigned long pdptr_bits = X86_CR4_PGE | X86_CR4_PSE | X86_CR4_PAE;
-
+	unsigned long pdptr_bits = X86_CR4_PGE | X86_CR4_PSE |
+				   X86_CR4_PAE | X86_CR4_SMEP;
 	if (cr4 & CR4_RESERVED_BITS)
 		return 1;
 
 	if (!guest_cpuid_has_xsave(vcpu) && (cr4 & X86_CR4_OSXSAVE))
 		return 1;
 
+	if (!guest_cpuid_has_smep(vcpu) && (cr4 & X86_CR4_SMEP))
+		return 1;
+
+	if (!guest_cpuid_has_fsgsbase(vcpu) && (cr4 & X86_CR4_RDWRGSFS))
+		return 1;
+
 	if (is_long_mode(vcpu)) {
 		if (!(cr4 & X86_CR4_PAE))
 			return 1;
@@ -615,11 +638,9 @@ int kvm_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4)
 				   kvm_read_cr3(vcpu)))
 		return 1;
 
-	if (cr4 & X86_CR4_VMXE)
+	if (kvm_x86_ops->set_cr4(vcpu, cr4))
 		return 1;
 
-	kvm_x86_ops->set_cr4(vcpu, cr4);
-
 	if ((cr4 ^ old_cr4) & pdptr_bits)
 		kvm_mmu_reset_context(vcpu);
 
@@ -787,12 +808,12 @@ EXPORT_SYMBOL_GPL(kvm_get_dr);
  * kvm-specific. Those are put in the beginning of the list.
  */
 
-#define KVM_SAVE_MSRS_BEGIN	8
+#define KVM_SAVE_MSRS_BEGIN	9
 static u32 msrs_to_save[] = {
 	MSR_KVM_SYSTEM_TIME, MSR_KVM_WALL_CLOCK,
 	MSR_KVM_SYSTEM_TIME_NEW, MSR_KVM_WALL_CLOCK_NEW,
 	HV_X64_MSR_GUEST_OS_ID, HV_X64_MSR_HYPERCALL,
-	HV_X64_MSR_APIC_ASSIST_PAGE, MSR_KVM_ASYNC_PF_EN,
+	HV_X64_MSR_APIC_ASSIST_PAGE, MSR_KVM_ASYNC_PF_EN, MSR_KVM_STEAL_TIME,
 	MSR_IA32_SYSENTER_CS, MSR_IA32_SYSENTER_ESP, MSR_IA32_SYSENTER_EIP,
 	MSR_STAR,
 #ifdef CONFIG_X86_64
@@ -1388,7 +1409,7 @@ static int set_msr_hyperv_pw(struct kvm_vcpu *vcpu, u32 msr, u64 data)
 			return 1;
 		kvm_x86_ops->patch_hypercall(vcpu, instructions);
 		((unsigned char *)instructions)[3] = 0xc3; /* ret */
-		if (copy_to_user((void __user *)addr, instructions, 4))
+		if (__copy_to_user((void __user *)addr, instructions, 4))
 			return 1;
 		kvm->arch.hv_hypercall = data;
 		break;
@@ -1415,7 +1436,7 @@ static int set_msr_hyperv(struct kvm_vcpu *vcpu, u32 msr, u64 data)
 				  HV_X64_MSR_APIC_ASSIST_PAGE_ADDRESS_SHIFT);
 		if (kvm_is_error_hva(addr))
 			return 1;
-		if (clear_user((void __user *)addr, PAGE_SIZE))
+		if (__clear_user((void __user *)addr, PAGE_SIZE))
 			return 1;
 		vcpu->arch.hv_vapic = data;
 		break;
@@ -1467,6 +1488,35 @@ static void kvmclock_reset(struct kvm_vcpu *vcpu)
 	}
 }
 
+static void accumulate_steal_time(struct kvm_vcpu *vcpu)
+{
+	u64 delta;
+
+	if (!(vcpu->arch.st.msr_val & KVM_MSR_ENABLED))
+		return;
+
+	delta = current->sched_info.run_delay - vcpu->arch.st.last_steal;
+	vcpu->arch.st.last_steal = current->sched_info.run_delay;
+	vcpu->arch.st.accum_steal = delta;
+}
+
+static void record_steal_time(struct kvm_vcpu *vcpu)
+{
+	if (!(vcpu->arch.st.msr_val & KVM_MSR_ENABLED))
+		return;
+
+	if (unlikely(kvm_read_guest_cached(vcpu->kvm, &vcpu->arch.st.stime,
+		&vcpu->arch.st.steal, sizeof(struct kvm_steal_time))))
+		return;
+
+	vcpu->arch.st.steal.steal += vcpu->arch.st.accum_steal;
+	vcpu->arch.st.steal.version += 2;
+	vcpu->arch.st.accum_steal = 0;
+
+	kvm_write_guest_cached(vcpu->kvm, &vcpu->arch.st.stime,
+		&vcpu->arch.st.steal, sizeof(struct kvm_steal_time));
+}
+
 int kvm_set_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 data)
 {
 	switch (msr) {
@@ -1549,6 +1599,33 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 data)
 		if (kvm_pv_enable_async_pf(vcpu, data))
 			return 1;
 		break;
+	case MSR_KVM_STEAL_TIME:
+
+		if (unlikely(!sched_info_on()))
+			return 1;
+
+		if (data & KVM_STEAL_RESERVED_MASK)
+			return 1;
+
+		if (kvm_gfn_to_hva_cache_init(vcpu->kvm, &vcpu->arch.st.stime,
+							data & KVM_STEAL_VALID_BITS))
+			return 1;
+
+		vcpu->arch.st.msr_val = data;
+
+		if (!(data & KVM_MSR_ENABLED))
+			break;
+
+		vcpu->arch.st.last_steal = current->sched_info.run_delay;
+
+		preempt_disable();
+		accumulate_steal_time(vcpu);
+		preempt_enable();
+
+		kvm_make_request(KVM_REQ_STEAL_UPDATE, vcpu);
+
+		break;
+
 	case MSR_IA32_MCG_CTL:
 	case MSR_IA32_MCG_STATUS:
 	case MSR_IA32_MC0_CTL ... MSR_IA32_MC0_CTL + 4 * KVM_MAX_MCE_BANKS - 1:
@@ -1834,6 +1911,9 @@ int kvm_get_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata)
 	case MSR_KVM_ASYNC_PF_EN:
 		data = vcpu->arch.apf.msr_val;
 		break;
+	case MSR_KVM_STEAL_TIME:
+		data = vcpu->arch.st.msr_val;
+		break;
 	case MSR_IA32_P5_MC_ADDR:
 	case MSR_IA32_P5_MC_TYPE:
 	case MSR_IA32_MCG_CAP:
@@ -2145,6 +2225,9 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
 			kvm_migrate_timers(vcpu);
 		vcpu->cpu = cpu;
 	}
+
+	accumulate_steal_time(vcpu);
+	kvm_make_request(KVM_REQ_STEAL_UPDATE, vcpu);
 }
 
 void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
@@ -2283,6 +2366,13 @@ static void do_cpuid_1_ent(struct kvm_cpuid_entry2 *entry, u32 function,
 	entry->flags = 0;
 }
 
+static bool supported_xcr0_bit(unsigned bit)
+{
+	u64 mask = ((u64)1 << bit);
+
+	return mask & (XSTATE_FP | XSTATE_SSE | XSTATE_YMM) & host_xcr0;
+}
+
 #define F(x) bit(X86_FEATURE_##x)
 
 static void do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
@@ -2328,7 +2418,7 @@ static void do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
 		0 /* Reserved, DCA */ | F(XMM4_1) |
 		F(XMM4_2) | F(X2APIC) | F(MOVBE) | F(POPCNT) |
 		0 /* Reserved*/ | F(AES) | F(XSAVE) | 0 /* OSXSAVE */ | F(AVX) |
-		F(F16C);
+		F(F16C) | F(RDRAND);
 	/* cpuid 0x80000001.ecx */
 	const u32 kvm_supported_word6_x86_features =
 		F(LAHF_LM) | F(CMP_LEGACY) | 0 /*SVM*/ | 0 /* ExtApicSpace */ |
@@ -2342,6 +2432,10 @@ static void do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
 		F(ACE2) | F(ACE2_EN) | F(PHE) | F(PHE_EN) |
 		F(PMM) | F(PMM_EN);
 
+	/* cpuid 7.0.ebx */
+	const u32 kvm_supported_word9_x86_features =
+		F(SMEP) | F(FSGSBASE) | F(ERMS);
+
 	/* all calls to cpuid_count() should be made on the same cpu */
 	get_cpu();
 	do_cpuid_1_ent(entry, function, index);
@@ -2376,7 +2470,7 @@ static void do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
 		}
 		break;
 	}
-	/* function 4 and 0xb have additional index. */
+	/* function 4 has additional index. */
 	case 4: {
 		int i, cache_type;
 
@@ -2393,6 +2487,22 @@ static void do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
 		}
 		break;
 	}
+	case 7: {
+		entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
+		/* Mask ebx against host capbability word 9 */
+		if (index == 0) {
+			entry->ebx &= kvm_supported_word9_x86_features;
+			cpuid_mask(&entry->ebx, 9);
+		} else
+			entry->ebx = 0;
+		entry->eax = 0;
+		entry->ecx = 0;
+		entry->edx = 0;
+		break;
+	}
+	case 9:
+		break;
+	/* function 0xb has additional index. */
 	case 0xb: {
 		int i, level_type;
 
@@ -2410,16 +2520,17 @@ static void do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
 		break;
 	}
 	case 0xd: {
-		int i;
+		int idx, i;
 
 		entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
-		for (i = 1; *nent < maxnent && i < 64; ++i) {
-			if (entry[i].eax == 0)
+		for (idx = 1, i = 1; *nent < maxnent && idx < 64; ++idx) {
+			do_cpuid_1_ent(&entry[i], function, idx);
+			if (entry[i].eax == 0 || !supported_xcr0_bit(idx))
 				continue;
-			do_cpuid_1_ent(&entry[i], function, i);
 			entry[i].flags |=
 			       KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
 			++*nent;
+			++i;
 		}
 		break;
 	}
@@ -2438,6 +2549,10 @@ static void do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
 			     (1 << KVM_FEATURE_CLOCKSOURCE2) |
 			     (1 << KVM_FEATURE_ASYNC_PF) |
 			     (1 << KVM_FEATURE_CLOCKSOURCE_STABLE_BIT);
+
+		if (sched_info_on())
+			entry->eax |= (1 << KVM_FEATURE_STEAL_TIME);
+
 		entry->ebx = 0;
 		entry->ecx = 0;
 		entry->edx = 0;
@@ -2451,6 +2566,24 @@ static void do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
 		entry->ecx &= kvm_supported_word6_x86_features;
 		cpuid_mask(&entry->ecx, 6);
 		break;
+	case 0x80000008: {
+		unsigned g_phys_as = (entry->eax >> 16) & 0xff;
+		unsigned virt_as = max((entry->eax >> 8) & 0xff, 48U);
+		unsigned phys_as = entry->eax & 0xff;
+
+		if (!g_phys_as)
+			g_phys_as = phys_as;
+		entry->eax = g_phys_as | (virt_as << 8);
+		entry->ebx = entry->edx = 0;
+		break;
+	}
+	case 0x80000019:
+		entry->ecx = entry->edx = 0;
+		break;
+	case 0x8000001a:
+		break;
+	case 0x8000001d:
+		break;
 	/*Add support for Centaur's CPUID instruction*/
 	case 0xC0000000:
 		/*Just support up to 0xC0000004 now*/
@@ -2460,10 +2593,16 @@ static void do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
 		entry->edx &= kvm_supported_word5_x86_features;
 		cpuid_mask(&entry->edx, 5);
 		break;
+	case 3: /* Processor serial number */
+	case 5: /* MONITOR/MWAIT */
+	case 6: /* Thermal management */
+	case 0xA: /* Architectural Performance Monitoring */
+	case 0x80000007: /* Advanced power management */
 	case 0xC0000002:
 	case 0xC0000003:
 	case 0xC0000004:
-		/*Now nothing to do, reserved for the future*/
+	default:
+		entry->eax = entry->ebx = entry->ecx = entry->edx = 0;
 		break;
 	}
 
@@ -3817,7 +3956,7 @@ static int kvm_fetch_guest_virt(struct x86_emulate_ctxt *ctxt,
 					  exception);
 }
 
-static int kvm_read_guest_virt(struct x86_emulate_ctxt *ctxt,
+int kvm_read_guest_virt(struct x86_emulate_ctxt *ctxt,
 			       gva_t addr, void *val, unsigned int bytes,
 			       struct x86_exception *exception)
 {
@@ -3827,6 +3966,7 @@ static int kvm_read_guest_virt(struct x86_emulate_ctxt *ctxt,
 	return kvm_read_guest_virt_helper(addr, val, bytes, vcpu, access,
 					  exception);
 }
+EXPORT_SYMBOL_GPL(kvm_read_guest_virt);
 
 static int kvm_read_guest_virt_system(struct x86_emulate_ctxt *ctxt,
 				      gva_t addr, void *val, unsigned int bytes,
@@ -3836,7 +3976,7 @@ static int kvm_read_guest_virt_system(struct x86_emulate_ctxt *ctxt,
 	return kvm_read_guest_virt_helper(addr, val, bytes, vcpu, 0, exception);
 }
 
-static int kvm_write_guest_virt_system(struct x86_emulate_ctxt *ctxt,
+int kvm_write_guest_virt_system(struct x86_emulate_ctxt *ctxt,
 				       gva_t addr, void *val,
 				       unsigned int bytes,
 				       struct x86_exception *exception)
@@ -3868,6 +4008,42 @@ static int kvm_write_guest_virt_system(struct x86_emulate_ctxt *ctxt,
 out:
 	return r;
 }
+EXPORT_SYMBOL_GPL(kvm_write_guest_virt_system);
+
+static int vcpu_mmio_gva_to_gpa(struct kvm_vcpu *vcpu, unsigned long gva,
+				gpa_t *gpa, struct x86_exception *exception,
+				bool write)
+{
+	u32 access = (kvm_x86_ops->get_cpl(vcpu) == 3) ? PFERR_USER_MASK : 0;
+
+	if (vcpu_match_mmio_gva(vcpu, gva) &&
+		  check_write_user_access(vcpu, write, access,
+		  vcpu->arch.access)) {
+		*gpa = vcpu->arch.mmio_gfn << PAGE_SHIFT |
+					(gva & (PAGE_SIZE - 1));
+		trace_vcpu_match_mmio(gva, *gpa, write, false);
+		return 1;
+	}
+
+	if (write)
+		access |= PFERR_WRITE_MASK;
+
+	*gpa = vcpu->arch.walk_mmu->gva_to_gpa(vcpu, gva, access, exception);
+
+	if (*gpa == UNMAPPED_GVA)
+		return -1;
+
+	/* For APIC access vmexit */
+	if ((*gpa & PAGE_MASK) == APIC_DEFAULT_PHYS_BASE)
+		return 1;
+
+	if (vcpu_match_mmio_gpa(vcpu, *gpa)) {
+		trace_vcpu_match_mmio(gva, *gpa, write, true);
+		return 1;
+	}
+
+	return 0;
+}
 
 static int emulator_read_emulated(struct x86_emulate_ctxt *ctxt,
 				  unsigned long addr,
@@ -3876,8 +4052,8 @@ static int emulator_read_emulated(struct x86_emulate_ctxt *ctxt,
 				  struct x86_exception *exception)
 {
 	struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt);
-	gpa_t                 gpa;
-	int handled;
+	gpa_t gpa;
+	int handled, ret;
 
 	if (vcpu->mmio_read_completed) {
 		memcpy(val, vcpu->mmio_data, bytes);
@@ -3887,13 +4063,12 @@ static int emulator_read_emulated(struct x86_emulate_ctxt *ctxt,
 		return X86EMUL_CONTINUE;
 	}
 
-	gpa = kvm_mmu_gva_to_gpa_read(vcpu, addr, exception);
+	ret = vcpu_mmio_gva_to_gpa(vcpu, addr, &gpa, exception, false);
 
-	if (gpa == UNMAPPED_GVA)
+	if (ret < 0)
 		return X86EMUL_PROPAGATE_FAULT;
 
-	/* For APIC access vmexit */
-	if ((gpa & PAGE_MASK) == APIC_DEFAULT_PHYS_BASE)
+	if (ret)
 		goto mmio;
 
 	if (kvm_read_guest_virt(ctxt, addr, val, bytes, exception)
@@ -3944,16 +4119,16 @@ static int emulator_write_emulated_onepage(unsigned long addr,
 					   struct x86_exception *exception,
 					   struct kvm_vcpu *vcpu)
 {
-	gpa_t                 gpa;
-	int handled;
+	gpa_t gpa;
+	int handled, ret;
 
-	gpa = kvm_mmu_gva_to_gpa_write(vcpu, addr, exception);
+	ret = vcpu_mmio_gva_to_gpa(vcpu, addr, &gpa, exception, true);
 
-	if (gpa == UNMAPPED_GVA)
+	if (ret < 0)
 		return X86EMUL_PROPAGATE_FAULT;
 
 	/* For APIC access vmexit */
-	if ((gpa & PAGE_MASK) == APIC_DEFAULT_PHYS_BASE)
+	if (ret)
 		goto mmio;
 
 	if (emulator_write_phys(vcpu, gpa, val, bytes))
@@ -4473,9 +4648,24 @@ static void inject_emulated_exception(struct kvm_vcpu *vcpu)
 		kvm_queue_exception(vcpu, ctxt->exception.vector);
 }
 
+static void init_decode_cache(struct x86_emulate_ctxt *ctxt,
+			      const unsigned long *regs)
+{
+	memset(&ctxt->twobyte, 0,
+	       (void *)&ctxt->regs - (void *)&ctxt->twobyte);
+	memcpy(ctxt->regs, regs, sizeof(ctxt->regs));
+
+	ctxt->fetch.start = 0;
+	ctxt->fetch.end = 0;
+	ctxt->io_read.pos = 0;
+	ctxt->io_read.end = 0;
+	ctxt->mem_read.pos = 0;
+	ctxt->mem_read.end = 0;
+}
+
 static void init_emulate_ctxt(struct kvm_vcpu *vcpu)
 {
-	struct decode_cache *c = &vcpu->arch.emulate_ctxt.decode;
+	struct x86_emulate_ctxt *ctxt = &vcpu->arch.emulate_ctxt;
 	int cs_db, cs_l;
 
 	/*
@@ -4488,40 +4678,38 @@ static void init_emulate_ctxt(struct kvm_vcpu *vcpu)
 
 	kvm_x86_ops->get_cs_db_l_bits(vcpu, &cs_db, &cs_l);
 
-	vcpu->arch.emulate_ctxt.eflags = kvm_get_rflags(vcpu);
-	vcpu->arch.emulate_ctxt.eip = kvm_rip_read(vcpu);
-	vcpu->arch.emulate_ctxt.mode =
-		(!is_protmode(vcpu)) ? X86EMUL_MODE_REAL :
-		(vcpu->arch.emulate_ctxt.eflags & X86_EFLAGS_VM)
-		? X86EMUL_MODE_VM86 : cs_l
-		? X86EMUL_MODE_PROT64 :	cs_db
-		? X86EMUL_MODE_PROT32 : X86EMUL_MODE_PROT16;
-	vcpu->arch.emulate_ctxt.guest_mode = is_guest_mode(vcpu);
-	memset(c, 0, sizeof(struct decode_cache));
-	memcpy(c->regs, vcpu->arch.regs, sizeof c->regs);
+	ctxt->eflags = kvm_get_rflags(vcpu);
+	ctxt->eip = kvm_rip_read(vcpu);
+	ctxt->mode = (!is_protmode(vcpu))		? X86EMUL_MODE_REAL :
+		     (ctxt->eflags & X86_EFLAGS_VM)	? X86EMUL_MODE_VM86 :
+		     cs_l				? X86EMUL_MODE_PROT64 :
+		     cs_db				? X86EMUL_MODE_PROT32 :
+							  X86EMUL_MODE_PROT16;
+	ctxt->guest_mode = is_guest_mode(vcpu);
+
+	init_decode_cache(ctxt, vcpu->arch.regs);
 	vcpu->arch.emulate_regs_need_sync_from_vcpu = false;
 }
 
 int kvm_inject_realmode_interrupt(struct kvm_vcpu *vcpu, int irq, int inc_eip)
 {
-	struct decode_cache *c = &vcpu->arch.emulate_ctxt.decode;
+	struct x86_emulate_ctxt *ctxt = &vcpu->arch.emulate_ctxt;
 	int ret;
 
 	init_emulate_ctxt(vcpu);
 
-	vcpu->arch.emulate_ctxt.decode.op_bytes = 2;
-	vcpu->arch.emulate_ctxt.decode.ad_bytes = 2;
-	vcpu->arch.emulate_ctxt.decode.eip = vcpu->arch.emulate_ctxt.eip +
-								 inc_eip;
-	ret = emulate_int_real(&vcpu->arch.emulate_ctxt, &emulate_ops, irq);
+	ctxt->op_bytes = 2;
+	ctxt->ad_bytes = 2;
+	ctxt->_eip = ctxt->eip + inc_eip;
+	ret = emulate_int_real(ctxt, irq);
 
 	if (ret != X86EMUL_CONTINUE)
 		return EMULATE_FAIL;
 
-	vcpu->arch.emulate_ctxt.eip = c->eip;
-	memcpy(vcpu->arch.regs, c->regs, sizeof c->regs);
-	kvm_rip_write(vcpu, vcpu->arch.emulate_ctxt.eip);
-	kvm_set_rflags(vcpu, vcpu->arch.emulate_ctxt.eflags);
+	ctxt->eip = ctxt->_eip;
+	memcpy(vcpu->arch.regs, ctxt->regs, sizeof ctxt->regs);
+	kvm_rip_write(vcpu, ctxt->eip);
+	kvm_set_rflags(vcpu, ctxt->eflags);
 
 	if (irq == NMI_VECTOR)
 		vcpu->arch.nmi_pending = false;
@@ -4582,21 +4770,21 @@ int x86_emulate_instruction(struct kvm_vcpu *vcpu,
 			    int insn_len)
 {
 	int r;
-	struct decode_cache *c = &vcpu->arch.emulate_ctxt.decode;
+	struct x86_emulate_ctxt *ctxt = &vcpu->arch.emulate_ctxt;
 	bool writeback = true;
 
 	kvm_clear_exception_queue(vcpu);
 
 	if (!(emulation_type & EMULTYPE_NO_DECODE)) {
 		init_emulate_ctxt(vcpu);
-		vcpu->arch.emulate_ctxt.interruptibility = 0;
-		vcpu->arch.emulate_ctxt.have_exception = false;
-		vcpu->arch.emulate_ctxt.perm_ok = false;
+		ctxt->interruptibility = 0;
+		ctxt->have_exception = false;
+		ctxt->perm_ok = false;
 
-		vcpu->arch.emulate_ctxt.only_vendor_specific_insn
+		ctxt->only_vendor_specific_insn
 			= emulation_type & EMULTYPE_TRAP_UD;
 
-		r = x86_decode_insn(&vcpu->arch.emulate_ctxt, insn, insn_len);
+		r = x86_decode_insn(ctxt, insn, insn_len);
 
 		trace_kvm_emulate_insn_start(vcpu);
 		++vcpu->stat.insn_emulation;
@@ -4612,7 +4800,7 @@ int x86_emulate_instruction(struct kvm_vcpu *vcpu,
 	}
 
 	if (emulation_type & EMULTYPE_SKIP) {
-		kvm_rip_write(vcpu, vcpu->arch.emulate_ctxt.decode.eip);
+		kvm_rip_write(vcpu, ctxt->_eip);
 		return EMULATE_DONE;
 	}
 
@@ -4620,11 +4808,11 @@ int x86_emulate_instruction(struct kvm_vcpu *vcpu,
 	   changes registers values  during IO operation */
 	if (vcpu->arch.emulate_regs_need_sync_from_vcpu) {
 		vcpu->arch.emulate_regs_need_sync_from_vcpu = false;
-		memcpy(c->regs, vcpu->arch.regs, sizeof c->regs);
+		memcpy(ctxt->regs, vcpu->arch.regs, sizeof ctxt->regs);
 	}
 
 restart:
-	r = x86_emulate_insn(&vcpu->arch.emulate_ctxt);
+	r = x86_emulate_insn(ctxt);
 
 	if (r == EMULATION_INTERCEPTED)
 		return EMULATE_DONE;
@@ -4636,7 +4824,7 @@ restart:
 		return handle_emulation_failure(vcpu);
 	}
 
-	if (vcpu->arch.emulate_ctxt.have_exception) {
+	if (ctxt->have_exception) {
 		inject_emulated_exception(vcpu);
 		r = EMULATE_DONE;
 	} else if (vcpu->arch.pio.count) {
@@ -4655,13 +4843,12 @@ restart:
 		r = EMULATE_DONE;
 
 	if (writeback) {
-		toggle_interruptibility(vcpu,
-				vcpu->arch.emulate_ctxt.interruptibility);
-		kvm_set_rflags(vcpu, vcpu->arch.emulate_ctxt.eflags);
+		toggle_interruptibility(vcpu, ctxt->interruptibility);
+		kvm_set_rflags(vcpu, ctxt->eflags);
 		kvm_make_request(KVM_REQ_EVENT, vcpu);
-		memcpy(vcpu->arch.regs, c->regs, sizeof c->regs);
+		memcpy(vcpu->arch.regs, ctxt->regs, sizeof ctxt->regs);
 		vcpu->arch.emulate_regs_need_sync_to_vcpu = false;
-		kvm_rip_write(vcpu, vcpu->arch.emulate_ctxt.eip);
+		kvm_rip_write(vcpu, ctxt->eip);
 	} else
 		vcpu->arch.emulate_regs_need_sync_to_vcpu = true;
 
@@ -4878,6 +5065,30 @@ void kvm_after_handle_nmi(struct kvm_vcpu *vcpu)
 }
 EXPORT_SYMBOL_GPL(kvm_after_handle_nmi);
 
+static void kvm_set_mmio_spte_mask(void)
+{
+	u64 mask;
+	int maxphyaddr = boot_cpu_data.x86_phys_bits;
+
+	/*
+	 * Set the reserved bits and the present bit of an paging-structure
+	 * entry to generate page fault with PFER.RSV = 1.
+	 */
+	mask = ((1ull << (62 - maxphyaddr + 1)) - 1) << maxphyaddr;
+	mask |= 1ull;
+
+#ifdef CONFIG_X86_64
+	/*
+	 * If reserved bit is not supported, clear the present bit to disable
+	 * mmio page fault.
+	 */
+	if (maxphyaddr == 52)
+		mask &= ~1ull;
+#endif
+
+	kvm_mmu_set_mmio_spte_mask(mask);
+}
+
 int kvm_arch_init(void *opaque)
 {
 	int r;
@@ -4904,10 +5115,10 @@ int kvm_arch_init(void *opaque)
 	if (r)
 		goto out;
 
+	kvm_set_mmio_spte_mask();
 	kvm_init_msr_list();
 
 	kvm_x86_ops = ops;
-	kvm_mmu_set_nonpresent_ptes(0ull, 0ull);
 	kvm_mmu_set_mask_ptes(PT_USER_MASK, PT_ACCESSED_MASK,
 			PT_DIRTY_MASK, PT64_NX_MASK, 0);
 
@@ -5082,8 +5293,7 @@ int emulator_fix_hypercall(struct x86_emulate_ctxt *ctxt)
 
 	kvm_x86_ops->patch_hypercall(vcpu, instruction);
 
-	return emulator_write_emulated(&vcpu->arch.emulate_ctxt,
-				       rip, instruction, 3, NULL);
+	return emulator_write_emulated(ctxt, rip, instruction, 3, NULL);
 }
 
 static int move_to_next_stateful_cpuid_entry(struct kvm_vcpu *vcpu, int i)
@@ -5384,6 +5594,9 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
 			r = 1;
 			goto out;
 		}
+		if (kvm_check_request(KVM_REQ_STEAL_UPDATE, vcpu))
+			record_steal_time(vcpu);
+
 	}
 
 	r = kvm_mmu_reload(vcpu);
@@ -5671,8 +5884,8 @@ int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
 		 * that usually, but some bad designed PV devices (vmware
 		 * backdoor interface) need this to work
 		 */
-		struct decode_cache *c = &vcpu->arch.emulate_ctxt.decode;
-		memcpy(vcpu->arch.regs, c->regs, sizeof c->regs);
+		struct x86_emulate_ctxt *ctxt = &vcpu->arch.emulate_ctxt;
+		memcpy(vcpu->arch.regs, ctxt->regs, sizeof ctxt->regs);
 		vcpu->arch.emulate_regs_need_sync_to_vcpu = false;
 	}
 	regs->rax = kvm_register_read(vcpu, VCPU_REGS_RAX);
@@ -5801,21 +6014,20 @@ int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
 int kvm_task_switch(struct kvm_vcpu *vcpu, u16 tss_selector, int reason,
 		    bool has_error_code, u32 error_code)
 {
-	struct decode_cache *c = &vcpu->arch.emulate_ctxt.decode;
+	struct x86_emulate_ctxt *ctxt = &vcpu->arch.emulate_ctxt;
 	int ret;
 
 	init_emulate_ctxt(vcpu);
 
-	ret = emulator_task_switch(&vcpu->arch.emulate_ctxt,
-				   tss_selector, reason, has_error_code,
-				   error_code);
+	ret = emulator_task_switch(ctxt, tss_selector, reason,
+				   has_error_code, error_code);
 
 	if (ret)
 		return EMULATE_FAIL;
 
-	memcpy(vcpu->arch.regs, c->regs, sizeof c->regs);
-	kvm_rip_write(vcpu, vcpu->arch.emulate_ctxt.eip);
-	kvm_set_rflags(vcpu, vcpu->arch.emulate_ctxt.eflags);
+	memcpy(vcpu->arch.regs, ctxt->regs, sizeof ctxt->regs);
+	kvm_rip_write(vcpu, ctxt->eip);
+	kvm_set_rflags(vcpu, ctxt->eflags);
 	kvm_make_request(KVM_REQ_EVENT, vcpu);
 	return EMULATE_DONE;
 }
@@ -6093,12 +6305,7 @@ int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu)
 	if (r == 0)
 		r = kvm_mmu_setup(vcpu);
 	vcpu_put(vcpu);
-	if (r < 0)
-		goto free_vcpu;
 
-	return 0;
-free_vcpu:
-	kvm_x86_ops->vcpu_free(vcpu);
 	return r;
 }
 
@@ -6126,6 +6333,7 @@ int kvm_arch_vcpu_reset(struct kvm_vcpu *vcpu)
 
 	kvm_make_request(KVM_REQ_EVENT, vcpu);
 	vcpu->arch.apf.msr_val = 0;
+	vcpu->arch.st.msr_val = 0;
 
 	kvmclock_reset(vcpu);
 
diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h
index e407ed3df817..d36fe237c665 100644
--- a/arch/x86/kvm/x86.h
+++ b/arch/x86/kvm/x86.h
@@ -75,10 +75,54 @@ static inline u32 bit(int bitno)
 	return 1 << (bitno & 31);
 }
 
+static inline void vcpu_cache_mmio_info(struct kvm_vcpu *vcpu,
+					gva_t gva, gfn_t gfn, unsigned access)
+{
+	vcpu->arch.mmio_gva = gva & PAGE_MASK;
+	vcpu->arch.access = access;
+	vcpu->arch.mmio_gfn = gfn;
+}
+
+/*
+ * Clear the mmio cache info for the given gva,
+ * specially, if gva is ~0ul, we clear all mmio cache info.
+ */
+static inline void vcpu_clear_mmio_info(struct kvm_vcpu *vcpu, gva_t gva)
+{
+	if (gva != (~0ul) && vcpu->arch.mmio_gva != (gva & PAGE_MASK))
+		return;
+
+	vcpu->arch.mmio_gva = 0;
+}
+
+static inline bool vcpu_match_mmio_gva(struct kvm_vcpu *vcpu, unsigned long gva)
+{
+	if (vcpu->arch.mmio_gva && vcpu->arch.mmio_gva == (gva & PAGE_MASK))
+		return true;
+
+	return false;
+}
+
+static inline bool vcpu_match_mmio_gpa(struct kvm_vcpu *vcpu, gpa_t gpa)
+{
+	if (vcpu->arch.mmio_gfn && vcpu->arch.mmio_gfn == gpa >> PAGE_SHIFT)
+		return true;
+
+	return false;
+}
+
 void kvm_before_handle_nmi(struct kvm_vcpu *vcpu);
 void kvm_after_handle_nmi(struct kvm_vcpu *vcpu);
 int kvm_inject_realmode_interrupt(struct kvm_vcpu *vcpu, int irq, int inc_eip);
 
 void kvm_write_tsc(struct kvm_vcpu *vcpu, u64 data);
 
+int kvm_read_guest_virt(struct x86_emulate_ctxt *ctxt,
+	gva_t addr, void *val, unsigned int bytes,
+	struct x86_exception *exception);
+
+int kvm_write_guest_virt_system(struct x86_emulate_ctxt *ctxt,
+	gva_t addr, void *val, unsigned int bytes,
+	struct x86_exception *exception);
+
 #endif
author	Linus Torvalds <torvalds@linux-foundation.org>	2011-07-24 09:07:03 -0700
committer	Linus Torvalds <torvalds@linux-foundation.org>	2011-07-24 09:07:03 -0700
commit	5fabc487c96819dd12ddb9414835d170fd9cd6d5 (patch)
tree	01532d492e5074b0d3add29bf92ebf9a9d161e9e /arch/x86
parent	c61264f98c1a974ee6f545f61a4ab33b141d6bda (diff)
parent	3f68b0318bbbd61bf08478ab99a149f0d9e5156e (diff)
download	blackbird-op-linux-5fabc487c96819dd12ddb9414835d170fd9cd6d5.tar.gz blackbird-op-linux-5fabc487c96819dd12ddb9414835d170fd9cd6d5.zip