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-rw-r--r--arch/x86/include/asm/kvm_host.h1
-rw-r--r--arch/x86/kvm/cpuid.c12
-rw-r--r--arch/x86/kvm/cpuid.h9
-rw-r--r--arch/x86/kvm/lapic.c2
-rw-r--r--arch/x86/kvm/smm.c2
-rw-r--r--arch/x86/kvm/svm/sev.c2
-rw-r--r--arch/x86/kvm/svm/svm.c2
-rw-r--r--arch/x86/kvm/vmx/vmx.c2
-rw-r--r--arch/x86/kvm/x86.c6
9 files changed, 27 insertions, 11 deletions
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index c4e844b60b0f..94b14b3a3b8d 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -879,6 +879,7 @@ struct kvm_vcpu_arch {
int cpuid_nent;
struct kvm_cpuid_entry2 *cpuid_entries;
+ bool cpuid_dynamic_bits_dirty;
bool is_amd_compatible;
/*
diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index 0de3f581ef12..97a90689a9dc 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -195,6 +195,7 @@ static int kvm_check_cpuid(struct kvm_vcpu *vcpu)
}
static u32 kvm_apply_cpuid_pv_features_quirk(struct kvm_vcpu *vcpu);
+static void kvm_update_cpuid_runtime(struct kvm_vcpu *vcpu);
/* Check whether the supplied CPUID data is equal to what is already set for the vCPU. */
static int kvm_cpuid_check_equal(struct kvm_vcpu *vcpu, struct kvm_cpuid_entry2 *e2,
@@ -299,10 +300,12 @@ static __always_inline void kvm_update_feature_runtime(struct kvm_vcpu *vcpu,
guest_cpu_cap_change(vcpu, x86_feature, has_feature);
}
-void kvm_update_cpuid_runtime(struct kvm_vcpu *vcpu)
+static void kvm_update_cpuid_runtime(struct kvm_vcpu *vcpu)
{
struct kvm_cpuid_entry2 *best;
+ vcpu->arch.cpuid_dynamic_bits_dirty = false;
+
best = kvm_find_cpuid_entry(vcpu, 1);
if (best) {
kvm_update_feature_runtime(vcpu, best, X86_FEATURE_OSXSAVE,
@@ -332,7 +335,6 @@ void kvm_update_cpuid_runtime(struct kvm_vcpu *vcpu)
cpuid_entry_has(best, X86_FEATURE_XSAVEC)))
best->ebx = xstate_required_size(vcpu->arch.xcr0, true);
}
-EXPORT_SYMBOL_GPL(kvm_update_cpuid_runtime);
static bool kvm_cpuid_has_hyperv(struct kvm_vcpu *vcpu)
{
@@ -645,6 +647,9 @@ int kvm_vcpu_ioctl_get_cpuid2(struct kvm_vcpu *vcpu,
if (cpuid->nent < vcpu->arch.cpuid_nent)
return -E2BIG;
+ if (vcpu->arch.cpuid_dynamic_bits_dirty)
+ kvm_update_cpuid_runtime(vcpu);
+
if (copy_to_user(entries, vcpu->arch.cpuid_entries,
vcpu->arch.cpuid_nent * sizeof(struct kvm_cpuid_entry2)))
return -EFAULT;
@@ -1984,6 +1989,9 @@ bool kvm_cpuid(struct kvm_vcpu *vcpu, u32 *eax, u32 *ebx,
struct kvm_cpuid_entry2 *entry;
bool exact, used_max_basic = false;
+ if (vcpu->arch.cpuid_dynamic_bits_dirty)
+ kvm_update_cpuid_runtime(vcpu);
+
entry = kvm_find_cpuid_entry_index(vcpu, function, index);
exact = !!entry;
diff --git a/arch/x86/kvm/cpuid.h b/arch/x86/kvm/cpuid.h
index 67d80aa72d50..d2884162a46a 100644
--- a/arch/x86/kvm/cpuid.h
+++ b/arch/x86/kvm/cpuid.h
@@ -11,7 +11,6 @@ extern u32 kvm_cpu_caps[NR_KVM_CPU_CAPS] __read_mostly;
void kvm_set_cpu_caps(void);
void kvm_vcpu_after_set_cpuid(struct kvm_vcpu *vcpu);
-void kvm_update_cpuid_runtime(struct kvm_vcpu *vcpu);
struct kvm_cpuid_entry2 *kvm_find_cpuid_entry_index(struct kvm_vcpu *vcpu,
u32 function, u32 index);
struct kvm_cpuid_entry2 *kvm_find_cpuid_entry(struct kvm_vcpu *vcpu,
@@ -232,6 +231,14 @@ static __always_inline bool guest_cpu_cap_has(struct kvm_vcpu *vcpu,
{
unsigned int x86_leaf = __feature_leaf(x86_feature);
+ /*
+ * Except for MWAIT, querying dynamic feature bits is disallowed, so
+ * that KVM can defer runtime updates until the next CPUID emulation.
+ */
+ BUILD_BUG_ON(x86_feature == X86_FEATURE_APIC ||
+ x86_feature == X86_FEATURE_OSXSAVE ||
+ x86_feature == X86_FEATURE_OSPKE);
+
return vcpu->arch.cpu_caps[x86_leaf] & __feature_bit(x86_feature);
}
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 750bb89b20ac..9dbc0f5d9865 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -2586,7 +2586,7 @@ static void __kvm_apic_set_base(struct kvm_vcpu *vcpu, u64 value)
vcpu->arch.apic_base = value;
if ((old_value ^ value) & MSR_IA32_APICBASE_ENABLE)
- kvm_update_cpuid_runtime(vcpu);
+ vcpu->arch.cpuid_dynamic_bits_dirty = true;
if (!apic)
return;
diff --git a/arch/x86/kvm/smm.c b/arch/x86/kvm/smm.c
index e0ab7df27b66..699e551ec93b 100644
--- a/arch/x86/kvm/smm.c
+++ b/arch/x86/kvm/smm.c
@@ -358,7 +358,7 @@ void enter_smm(struct kvm_vcpu *vcpu)
goto error;
#endif
- kvm_update_cpuid_runtime(vcpu);
+ vcpu->arch.cpuid_dynamic_bits_dirty = true;
kvm_mmu_reset_context(vcpu);
return;
error:
diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
index 8bc62e994138..42a6d8bb1024 100644
--- a/arch/x86/kvm/svm/sev.c
+++ b/arch/x86/kvm/svm/sev.c
@@ -3261,7 +3261,7 @@ static void sev_es_sync_from_ghcb(struct vcpu_svm *svm)
if (kvm_ghcb_xcr0_is_valid(svm)) {
vcpu->arch.xcr0 = ghcb_get_xcr0(ghcb);
- kvm_update_cpuid_runtime(vcpu);
+ vcpu->arch.cpuid_dynamic_bits_dirty = true;
}
/* Copy the GHCB exit information into the VMCB fields */
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 7640a84e554a..88dd61389a2d 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -1932,7 +1932,7 @@ void svm_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4)
vmcb_mark_dirty(to_svm(vcpu)->vmcb, VMCB_CR);
if ((cr4 ^ old_cr4) & (X86_CR4_OSXSAVE | X86_CR4_PKE))
- kvm_update_cpuid_runtime(vcpu);
+ vcpu->arch.cpuid_dynamic_bits_dirty = true;
}
static void svm_set_segment(struct kvm_vcpu *vcpu,
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index f72835e85b6d..b60de7f8e563 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -3523,7 +3523,7 @@ void vmx_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4)
vmcs_writel(GUEST_CR4, hw_cr4);
if ((cr4 ^ old_cr4) & (X86_CR4_OSXSAVE | X86_CR4_PKE))
- kvm_update_cpuid_runtime(vcpu);
+ vcpu->arch.cpuid_dynamic_bits_dirty = true;
}
void vmx_get_segment(struct kvm_vcpu *vcpu, struct kvm_segment *var, int seg)
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 9883f0565baf..263ab2ec6f71 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -1264,7 +1264,7 @@ static int __kvm_set_xcr(struct kvm_vcpu *vcpu, u32 index, u64 xcr)
vcpu->arch.xcr0 = xcr0;
if ((xcr0 ^ old_xcr0) & XFEATURE_MASK_EXTEND)
- kvm_update_cpuid_runtime(vcpu);
+ vcpu->arch.cpuid_dynamic_bits_dirty = true;
return 0;
}
@@ -3899,7 +3899,7 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
if (!guest_cpu_cap_has(vcpu, X86_FEATURE_XMM3))
return 1;
vcpu->arch.ia32_misc_enable_msr = data;
- kvm_update_cpuid_runtime(vcpu);
+ vcpu->arch.cpuid_dynamic_bits_dirty = true;
} else {
vcpu->arch.ia32_misc_enable_msr = data;
}
@@ -3934,7 +3934,7 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
if (data & ~kvm_caps.supported_xss)
return 1;
vcpu->arch.ia32_xss = data;
- kvm_update_cpuid_runtime(vcpu);
+ vcpu->arch.cpuid_dynamic_bits_dirty = true;
break;
case MSR_SMI_COUNT:
if (!msr_info->host_initiated)
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