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-rw-r--r--drivers/kvm/kvm.h4
-rw-r--r--drivers/kvm/vmx.c128
2 files changed, 76 insertions, 56 deletions
diff --git a/drivers/kvm/kvm.h b/drivers/kvm/kvm.h
index fc4a6c1235f0..c252efed49d9 100644
--- a/drivers/kvm/kvm.h
+++ b/drivers/kvm/kvm.h
@@ -288,6 +288,10 @@ struct kvm_vcpu {
u64 apic_base;
u64 ia32_misc_enable_msr;
int nmsrs;
+ int save_nmsrs;
+#ifdef CONFIG_X86_64
+ int msr_offset_kernel_gs_base;
+#endif
struct vmx_msr_entry *guest_msrs;
struct vmx_msr_entry *host_msrs;
diff --git a/drivers/kvm/vmx.c b/drivers/kvm/vmx.c
index a05bfa085877..872ca0381fbe 100644
--- a/drivers/kvm/vmx.c
+++ b/drivers/kvm/vmx.c
@@ -85,19 +85,6 @@ static const u32 vmx_msr_index[] = {
};
#define NR_VMX_MSR ARRAY_SIZE(vmx_msr_index)
-#ifdef CONFIG_X86_64
-static unsigned msr_offset_kernel_gs_base;
-#define NR_64BIT_MSRS 4
-/*
- * avoid save/load MSR_SYSCALL_MASK and MSR_LSTAR by std vt
- * mechanism (cpu bug AA24)
- */
-#define NR_BAD_MSRS 2
-#else
-#define NR_64BIT_MSRS 0
-#define NR_BAD_MSRS 0
-#endif
-
static inline int is_page_fault(u32 intr_info)
{
return (intr_info & (INTR_INFO_INTR_TYPE_MASK | INTR_INFO_VECTOR_MASK |
@@ -118,13 +105,23 @@ static inline int is_external_interrupt(u32 intr_info)
== (INTR_TYPE_EXT_INTR | INTR_INFO_VALID_MASK);
}
-static struct vmx_msr_entry *find_msr_entry(struct kvm_vcpu *vcpu, u32 msr)
+static int __find_msr_index(struct kvm_vcpu *vcpu, u32 msr)
{
int i;
for (i = 0; i < vcpu->nmsrs; ++i)
if (vcpu->guest_msrs[i].index == msr)
- return &vcpu->guest_msrs[i];
+ return i;
+ return -1;
+}
+
+static struct vmx_msr_entry *find_msr_entry(struct kvm_vcpu *vcpu, u32 msr)
+{
+ int i;
+
+ i = __find_msr_index(vcpu, msr);
+ if (i >= 0)
+ return &vcpu->guest_msrs[i];
return NULL;
}
@@ -307,10 +304,10 @@ static void vmx_save_host_state(struct kvm_vcpu *vcpu)
#ifdef CONFIG_X86_64
if (is_long_mode(vcpu)) {
- save_msrs(vcpu->host_msrs + msr_offset_kernel_gs_base, 1);
- load_msrs(vcpu->guest_msrs, NR_BAD_MSRS);
+ save_msrs(vcpu->host_msrs + vcpu->msr_offset_kernel_gs_base, 1);
}
#endif
+ load_msrs(vcpu->guest_msrs, vcpu->save_nmsrs);
}
static void vmx_load_host_state(struct kvm_vcpu *vcpu)
@@ -337,12 +334,8 @@ static void vmx_load_host_state(struct kvm_vcpu *vcpu)
reload_tss();
}
-#ifdef CONFIG_X86_64
- if (is_long_mode(vcpu)) {
- save_msrs(vcpu->guest_msrs, NR_BAD_MSRS);
- load_msrs(vcpu->host_msrs, NR_BAD_MSRS);
- }
-#endif
+ save_msrs(vcpu->guest_msrs, vcpu->save_nmsrs);
+ load_msrs(vcpu->host_msrs, vcpu->save_nmsrs);
}
/*
@@ -464,41 +457,74 @@ static void vmx_inject_gp(struct kvm_vcpu *vcpu, unsigned error_code)
}
/*
+ * Swap MSR entry in host/guest MSR entry array.
+ */
+void move_msr_up(struct kvm_vcpu *vcpu, int from, int to)
+{
+ struct vmx_msr_entry tmp;
+ tmp = vcpu->guest_msrs[to];
+ vcpu->guest_msrs[to] = vcpu->guest_msrs[from];
+ vcpu->guest_msrs[from] = tmp;
+ tmp = vcpu->host_msrs[to];
+ vcpu->host_msrs[to] = vcpu->host_msrs[from];
+ vcpu->host_msrs[from] = tmp;
+}
+
+/*
* Set up the vmcs to automatically save and restore system
* msrs. Don't touch the 64-bit msrs if the guest is in legacy
* mode, as fiddling with msrs is very expensive.
*/
static void setup_msrs(struct kvm_vcpu *vcpu)
{
- int nr_skip, nr_good_msrs;
+ int index, save_nmsrs;
- if (is_long_mode(vcpu))
- nr_skip = NR_BAD_MSRS;
- else
- nr_skip = NR_64BIT_MSRS;
- nr_good_msrs = vcpu->nmsrs - nr_skip;
+ save_nmsrs = 0;
+#ifdef CONFIG_X86_64
+ if (is_long_mode(vcpu)) {
+ index = __find_msr_index(vcpu, MSR_SYSCALL_MASK);
+ if (index >= 0)
+ move_msr_up(vcpu, index, save_nmsrs++);
+ index = __find_msr_index(vcpu, MSR_LSTAR);
+ if (index >= 0)
+ move_msr_up(vcpu, index, save_nmsrs++);
+ index = __find_msr_index(vcpu, MSR_CSTAR);
+ if (index >= 0)
+ move_msr_up(vcpu, index, save_nmsrs++);
+ index = __find_msr_index(vcpu, MSR_KERNEL_GS_BASE);
+ if (index >= 0)
+ move_msr_up(vcpu, index, save_nmsrs++);
+ /*
+ * MSR_K6_STAR is only needed on long mode guests, and only
+ * if efer.sce is enabled.
+ */
+ index = __find_msr_index(vcpu, MSR_K6_STAR);
+ if ((index >= 0) && (vcpu->shadow_efer & EFER_SCE))
+ move_msr_up(vcpu, index, save_nmsrs++);
+ }
+#endif
+ vcpu->save_nmsrs = save_nmsrs;
- /*
- * MSR_K6_STAR is only needed on long mode guests, and only
- * if efer.sce is enabled.
- */
- if (find_msr_entry(vcpu, MSR_K6_STAR)) {
- --nr_good_msrs;
#ifdef CONFIG_X86_64
- if (is_long_mode(vcpu) && (vcpu->shadow_efer & EFER_SCE))
- ++nr_good_msrs;
+ vcpu->msr_offset_kernel_gs_base =
+ __find_msr_index(vcpu, MSR_KERNEL_GS_BASE);
#endif
+ index = __find_msr_index(vcpu, MSR_EFER);
+ if (index >= 0)
+ save_nmsrs = 1;
+ else {
+ save_nmsrs = 0;
+ index = 0;
}
-
vmcs_writel(VM_ENTRY_MSR_LOAD_ADDR,
- virt_to_phys(vcpu->guest_msrs + nr_skip));
+ virt_to_phys(vcpu->guest_msrs + index));
vmcs_writel(VM_EXIT_MSR_STORE_ADDR,
- virt_to_phys(vcpu->guest_msrs + nr_skip));
+ virt_to_phys(vcpu->guest_msrs + index));
vmcs_writel(VM_EXIT_MSR_LOAD_ADDR,
- virt_to_phys(vcpu->host_msrs + nr_skip));
- vmcs_write32(VM_EXIT_MSR_STORE_COUNT, nr_good_msrs); /* 22.2.2 */
- vmcs_write32(VM_EXIT_MSR_LOAD_COUNT, nr_good_msrs); /* 22.2.2 */
- vmcs_write32(VM_ENTRY_MSR_LOAD_COUNT, nr_good_msrs); /* 22.2.2 */
+ virt_to_phys(vcpu->host_msrs + index));
+ vmcs_write32(VM_EXIT_MSR_STORE_COUNT, save_nmsrs);
+ vmcs_write32(VM_EXIT_MSR_LOAD_COUNT, save_nmsrs);
+ vmcs_write32(VM_ENTRY_MSR_LOAD_COUNT, save_nmsrs);
}
/*
@@ -595,14 +621,6 @@ static int vmx_set_msr(struct kvm_vcpu *vcpu, u32 msr_index, u64 data)
case MSR_GS_BASE:
vmcs_writel(GUEST_GS_BASE, data);
break;
- case MSR_LSTAR:
- case MSR_SYSCALL_MASK:
- msr = find_msr_entry(vcpu, msr_index);
- if (msr)
- msr->data = data;
- if (vcpu->vmx_host_state.loaded)
- load_msrs(vcpu->guest_msrs, NR_BAD_MSRS);
- break;
#endif
case MSR_IA32_SYSENTER_CS:
vmcs_write32(GUEST_SYSENTER_CS, data);
@@ -620,6 +638,8 @@ static int vmx_set_msr(struct kvm_vcpu *vcpu, u32 msr_index, u64 data)
msr = find_msr_entry(vcpu, msr_index);
if (msr) {
msr->data = data;
+ if (vcpu->vmx_host_state.loaded)
+ load_msrs(vcpu->guest_msrs,vcpu->save_nmsrs);
break;
}
return kvm_set_msr_common(vcpu, msr_index, data);
@@ -1331,10 +1351,6 @@ static int vmx_vcpu_setup(struct kvm_vcpu *vcpu)
vcpu->host_msrs[j].reserved = 0;
vcpu->host_msrs[j].data = data;
vcpu->guest_msrs[j] = vcpu->host_msrs[j];
-#ifdef CONFIG_X86_64
- if (index == MSR_KERNEL_GS_BASE)
- msr_offset_kernel_gs_base = j;
-#endif
++vcpu->nmsrs;
}
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