From c735aa9b4375d37dbd61c7c655d6b007d7d1962c Mon Sep 17 00:00:00 2001 From: Vitaly Kuznetsov Date: Wed, 12 Jan 2022 14:27:54 +0100 Subject: [PATCH RFC 2/3] KVM: x86: Do runtime CPUID update before updating vcpu->arch.cpuid_entries Signed-off-by: Vitaly Kuznetsov --- arch/x86/kvm/cpuid.c | 35 +++++++++++++++++++++++++---------- 1 file changed, 25 insertions(+), 10 deletions(-) diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index 89af3c7390d3..16f4083edeeb 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -125,14 +125,21 @@ static void kvm_update_kvm_cpuid_base(struct kvm_vcpu *vcpu) } } -static struct kvm_cpuid_entry2 *kvm_find_kvm_cpuid_features(struct kvm_vcpu *vcpu) +static struct kvm_cpuid_entry2 *__kvm_find_kvm_cpuid_features(struct kvm_vcpu *vcpu, + struct kvm_cpuid_entry2 *entries, int nent) { u32 base = vcpu->arch.kvm_cpuid_base; if (!base) return NULL; - return kvm_find_cpuid_entry(vcpu, base | KVM_CPUID_FEATURES, 0); + return cpuid_entry2_find(entries, nent, base | KVM_CPUID_FEATURES, 0); +} + +static struct kvm_cpuid_entry2 *kvm_find_kvm_cpuid_features(struct kvm_vcpu *vcpu) +{ + return __kvm_find_kvm_cpuid_features(vcpu, vcpu->arch.cpuid_entries, + vcpu->arch.cpuid_nent); } void kvm_update_pv_runtime(struct kvm_vcpu *vcpu) @@ -147,11 +154,12 @@ void kvm_update_pv_runtime(struct kvm_vcpu *vcpu) vcpu->arch.pv_cpuid.features = best->eax; } -void kvm_update_cpuid_runtime(struct kvm_vcpu *vcpu) +static void __kvm_update_cpuid_runtime(struct kvm_vcpu *vcpu, struct kvm_cpuid_entry2 *entries, + int nent) { struct kvm_cpuid_entry2 *best; - best = kvm_find_cpuid_entry(vcpu, 1, 0); + best = cpuid_entry2_find(entries, nent, 1, 0); if (best) { /* Update OSXSAVE bit */ if (boot_cpu_has(X86_FEATURE_XSAVE)) @@ -162,33 +170,39 @@ void kvm_update_cpuid_runtime(struct kvm_vcpu *vcpu) vcpu->arch.apic_base & MSR_IA32_APICBASE_ENABLE); } - best = kvm_find_cpuid_entry(vcpu, 7, 0); + best = cpuid_entry2_find(entries, nent, 7, 0); if (best && boot_cpu_has(X86_FEATURE_PKU) && best->function == 0x7) cpuid_entry_change(best, X86_FEATURE_OSPKE, kvm_read_cr4_bits(vcpu, X86_CR4_PKE)); - best = kvm_find_cpuid_entry(vcpu, 0xD, 0); + best = cpuid_entry2_find(entries, nent, 0xD, 0); if (best) best->ebx = xstate_required_size(vcpu->arch.xcr0, false); - best = kvm_find_cpuid_entry(vcpu, 0xD, 1); + best = cpuid_entry2_find(entries, nent, 0xD, 1); if (best && (cpuid_entry_has(best, X86_FEATURE_XSAVES) || cpuid_entry_has(best, X86_FEATURE_XSAVEC))) best->ebx = xstate_required_size(vcpu->arch.xcr0, true); - best = kvm_find_kvm_cpuid_features(vcpu); + best = __kvm_find_kvm_cpuid_features(vcpu, vcpu->arch.cpuid_entries, + vcpu->arch.cpuid_nent); if (kvm_hlt_in_guest(vcpu->kvm) && best && (best->eax & (1 << KVM_FEATURE_PV_UNHALT))) best->eax &= ~(1 << KVM_FEATURE_PV_UNHALT); if (!kvm_check_has_quirk(vcpu->kvm, KVM_X86_QUIRK_MISC_ENABLE_NO_MWAIT)) { - best = kvm_find_cpuid_entry(vcpu, 0x1, 0); + best = cpuid_entry2_find(entries, nent, 0x1, 0); if (best) cpuid_entry_change(best, X86_FEATURE_MWAIT, vcpu->arch.ia32_misc_enable_msr & MSR_IA32_MISC_ENABLE_MWAIT); } } + +void kvm_update_cpuid_runtime(struct kvm_vcpu *vcpu) +{ + __kvm_update_cpuid_runtime(vcpu, vcpu->arch.cpuid_entries, vcpu->arch.cpuid_nent); +} EXPORT_SYMBOL_GPL(kvm_update_cpuid_runtime); static void kvm_vcpu_after_set_cpuid(struct kvm_vcpu *vcpu) @@ -278,6 +292,8 @@ static int kvm_set_cpuid(struct kvm_vcpu *vcpu, struct kvm_cpuid_entry2 *e2, { int r; + __kvm_update_cpuid_runtime(vcpu, e2, nent); + r = kvm_check_cpuid(e2, nent); if (r) return r; @@ -287,7 +303,6 @@ static int kvm_set_cpuid(struct kvm_vcpu *vcpu, struct kvm_cpuid_entry2 *e2, vcpu->arch.cpuid_nent = nent; kvm_update_kvm_cpuid_base(vcpu); - kvm_update_cpuid_runtime(vcpu); kvm_vcpu_after_set_cpuid(vcpu); return 0; -- 2.34.1