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-rw-r--r--arch/x86/kernel/cpu/common.c3
-rw-r--r--arch/x86/kernel/cpu/mshyperv.c22
-rw-r--r--arch/x86/kernel/kvm.c18
-rw-r--r--arch/x86/kernel/process_64.c14
4 files changed, 48 insertions, 9 deletions
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 348cf4821240..4702fbd98f92 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -487,7 +487,7 @@ void load_percpu_segment(int cpu)
loadsegment(fs, __KERNEL_PERCPU);
#else
__loadsegment_simple(gs, 0);
- wrmsrl(MSR_GS_BASE, (unsigned long)per_cpu(irq_stack_union.gs_base, cpu));
+ wrmsrl(MSR_GS_BASE, cpu_kernelmode_gs_base(cpu));
#endif
load_stack_canary_segment();
}
@@ -1398,6 +1398,7 @@ __setup("clearcpuid=", setup_clearcpuid);
#ifdef CONFIG_X86_64
DEFINE_PER_CPU_FIRST(union irq_stack_union,
irq_stack_union) __aligned(PAGE_SIZE) __visible;
+EXPORT_PER_CPU_SYMBOL_GPL(irq_stack_union);
/*
* The following percpu variables are hot. Align current_task to
diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c
index 4488cf0dd499..031082c96db8 100644
--- a/arch/x86/kernel/cpu/mshyperv.c
+++ b/arch/x86/kernel/cpu/mshyperv.c
@@ -22,7 +22,7 @@
#include <linux/kexec.h>
#include <asm/processor.h>
#include <asm/hypervisor.h>
-#include <asm/hyperv.h>
+#include <asm/hyperv-tlfs.h>
#include <asm/mshyperv.h>
#include <asm/desc.h>
#include <asm/irq_regs.h>
@@ -216,8 +216,8 @@ static void __init ms_hyperv_init_platform(void)
pr_info("Hyper-V: features 0x%x, hints 0x%x\n",
ms_hyperv.features, ms_hyperv.hints);
- ms_hyperv.max_vp_index = cpuid_eax(HVCPUID_IMPLEMENTATION_LIMITS);
- ms_hyperv.max_lp_index = cpuid_ebx(HVCPUID_IMPLEMENTATION_LIMITS);
+ ms_hyperv.max_vp_index = cpuid_eax(HYPERV_CPUID_IMPLEMENT_LIMITS);
+ ms_hyperv.max_lp_index = cpuid_ebx(HYPERV_CPUID_IMPLEMENT_LIMITS);
pr_debug("Hyper-V: max %u virtual processors, %u logical processors\n",
ms_hyperv.max_vp_index, ms_hyperv.max_lp_index);
@@ -225,11 +225,12 @@ static void __init ms_hyperv_init_platform(void)
/*
* Extract host information.
*/
- if (cpuid_eax(HVCPUID_VENDOR_MAXFUNCTION) >= HVCPUID_VERSION) {
- hv_host_info_eax = cpuid_eax(HVCPUID_VERSION);
- hv_host_info_ebx = cpuid_ebx(HVCPUID_VERSION);
- hv_host_info_ecx = cpuid_ecx(HVCPUID_VERSION);
- hv_host_info_edx = cpuid_edx(HVCPUID_VERSION);
+ if (cpuid_eax(HYPERV_CPUID_VENDOR_AND_MAX_FUNCTIONS) >=
+ HYPERV_CPUID_VERSION) {
+ hv_host_info_eax = cpuid_eax(HYPERV_CPUID_VERSION);
+ hv_host_info_ebx = cpuid_ebx(HYPERV_CPUID_VERSION);
+ hv_host_info_ecx = cpuid_ecx(HYPERV_CPUID_VERSION);
+ hv_host_info_edx = cpuid_edx(HYPERV_CPUID_VERSION);
pr_info("Hyper-V Host Build:%d-%d.%d-%d-%d.%d\n",
hv_host_info_eax, hv_host_info_ebx >> 16,
@@ -243,6 +244,11 @@ static void __init ms_hyperv_init_platform(void)
x86_platform.calibrate_cpu = hv_get_tsc_khz;
}
+ if (ms_hyperv.hints & HV_X64_ENLIGHTENED_VMCS_RECOMMENDED) {
+ ms_hyperv.nested_features =
+ cpuid_eax(HYPERV_CPUID_NESTED_FEATURES);
+ }
+
#ifdef CONFIG_X86_LOCAL_APIC
if (ms_hyperv.features & HV_X64_ACCESS_FREQUENCY_MSRS &&
ms_hyperv.misc_features & HV_FEATURE_FREQUENCY_MSRS_AVAILABLE) {
diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c
index fae86e36e399..7867417cfaff 100644
--- a/arch/x86/kernel/kvm.c
+++ b/arch/x86/kernel/kvm.c
@@ -454,6 +454,13 @@ static void __init sev_map_percpu_data(void)
}
#ifdef CONFIG_SMP
+static void __init kvm_smp_prepare_cpus(unsigned int max_cpus)
+{
+ native_smp_prepare_cpus(max_cpus);
+ if (kvm_para_has_hint(KVM_HINTS_DEDICATED))
+ static_branch_disable(&virt_spin_lock_key);
+}
+
static void __init kvm_smp_prepare_boot_cpu(void)
{
/*
@@ -546,6 +553,7 @@ static void __init kvm_guest_init(void)
}
if (kvm_para_has_feature(KVM_FEATURE_PV_TLB_FLUSH) &&
+ !kvm_para_has_hint(KVM_HINTS_DEDICATED) &&
kvm_para_has_feature(KVM_FEATURE_STEAL_TIME))
pv_mmu_ops.flush_tlb_others = kvm_flush_tlb_others;
@@ -556,6 +564,7 @@ static void __init kvm_guest_init(void)
kvm_setup_vsyscall_timeinfo();
#ifdef CONFIG_SMP
+ smp_ops.smp_prepare_cpus = kvm_smp_prepare_cpus;
smp_ops.smp_prepare_boot_cpu = kvm_smp_prepare_boot_cpu;
if (cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN, "x86/kvm:online",
kvm_cpu_online, kvm_cpu_down_prepare) < 0)
@@ -605,6 +614,11 @@ unsigned int kvm_arch_para_features(void)
return cpuid_eax(kvm_cpuid_base() | KVM_CPUID_FEATURES);
}
+unsigned int kvm_arch_para_hints(void)
+{
+ return cpuid_edx(kvm_cpuid_base() | KVM_CPUID_FEATURES);
+}
+
static uint32_t __init kvm_detect(void)
{
return kvm_cpuid_base();
@@ -635,6 +649,7 @@ static __init int kvm_setup_pv_tlb_flush(void)
int cpu;
if (kvm_para_has_feature(KVM_FEATURE_PV_TLB_FLUSH) &&
+ !kvm_para_has_hint(KVM_HINTS_DEDICATED) &&
kvm_para_has_feature(KVM_FEATURE_STEAL_TIME)) {
for_each_possible_cpu(cpu) {
zalloc_cpumask_var_node(per_cpu_ptr(&__pv_tlb_mask, cpu),
@@ -730,6 +745,9 @@ void __init kvm_spinlock_init(void)
if (!kvm_para_has_feature(KVM_FEATURE_PV_UNHALT))
return;
+ if (kvm_para_has_hint(KVM_HINTS_DEDICATED))
+ return;
+
__pv_init_lock_hash();
pv_lock_ops.queued_spin_lock_slowpath = __pv_queued_spin_lock_slowpath;
pv_lock_ops.queued_spin_unlock = PV_CALLEE_SAVE(__pv_queued_spin_unlock);
diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c
index 9eb448c7859d..4b100fe0f508 100644
--- a/arch/x86/kernel/process_64.c
+++ b/arch/x86/kernel/process_64.c
@@ -205,6 +205,20 @@ static __always_inline void save_fsgs(struct task_struct *task)
save_base_legacy(task, task->thread.gsindex, GS);
}
+#if IS_ENABLED(CONFIG_KVM)
+/*
+ * While a process is running,current->thread.fsbase and current->thread.gsbase
+ * may not match the corresponding CPU registers (see save_base_legacy()). KVM
+ * wants an efficient way to save and restore FSBASE and GSBASE.
+ * When FSGSBASE extensions are enabled, this will have to use RD{FS,GS}BASE.
+ */
+void save_fsgs_for_kvm(void)
+{
+ save_fsgs(current);
+}
+EXPORT_SYMBOL_GPL(save_fsgs_for_kvm);
+#endif
+
static __always_inline void loadseg(enum which_selector which,
unsigned short sel)
{
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