From: Sean Christopherson <seanjc@google.com> mainline inclusion from mainline-v6.11-rc1 commit 1028893a73fe20b2d1b90b4a6005b288286b9309 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/ICNFN5 CVE: CVE-2025-38351 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... -------------------------------- Move guest_cpuid_is_amd_or_hygon() into cpuid.c now that, except for one Intel quirk in the emulator, KVM checks for AMD vs. Intel *compatible* vCPUs, not exact vendors, i.e. now that there should not be any reason for KVM at-large to care about the exact vendor. Opportunistically refactor the guts of the helper to use "entry" instead of "best", and short circuit the !entry path to make the common case more readable. Link: https://lore.kernel.org/r/20240405235603.1173076-11-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com> Conflicts: arch/x86/kvm/cpuid.c [fix context conflicts] Signed-off-by: Lin Yujun <linyujun809@h-partners.com> --- arch/x86/kvm/cpuid.c | 12 ++++++++++++ arch/x86/kvm/cpuid.h | 10 ---------- 2 files changed, 12 insertions(+), 10 deletions(-) diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index 8291df97109e..851a9f85b9bb 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -342,6 +342,18 @@ static bool kvm_cpuid_has_hyperv(struct kvm_cpuid_entry2 *entries, int nent) return entry && entry->eax == HYPERV_CPUID_SIGNATURE_EAX; } +static bool guest_cpuid_is_amd_or_hygon(struct kvm_vcpu *vcpu) +{ + struct kvm_cpuid_entry2 *entry; + + entry = kvm_find_cpuid_entry(vcpu, 0); + if (!entry) + return false; + + return is_guest_vendor_amd(entry->ebx, entry->ecx, entry->edx) || + is_guest_vendor_hygon(entry->ebx, entry->ecx, entry->edx); +} + static void kvm_vcpu_after_set_cpuid(struct kvm_vcpu *vcpu) { struct kvm_lapic *apic = vcpu->arch.apic; diff --git a/arch/x86/kvm/cpuid.h b/arch/x86/kvm/cpuid.h index 59a15b4292aa..986a91da2c43 100644 --- a/arch/x86/kvm/cpuid.h +++ b/arch/x86/kvm/cpuid.h @@ -103,16 +103,6 @@ static __always_inline void guest_cpuid_clear(struct kvm_vcpu *vcpu, *reg &= ~__feature_bit(x86_feature); } -static inline bool guest_cpuid_is_amd_or_hygon(struct kvm_vcpu *vcpu) -{ - struct kvm_cpuid_entry2 *best; - - best = kvm_find_cpuid_entry(vcpu, 0); - return best && - (is_guest_vendor_amd(best->ebx, best->ecx, best->edx) || - is_guest_vendor_hygon(best->ebx, best->ecx, best->edx)); -} - static inline bool guest_cpuid_is_amd_compatible(struct kvm_vcpu *vcpu) { return vcpu->arch.is_amd_compatible; -- 2.34.1