
From: Sean Christopherson <seanjc@google.com> mainline inclusion from mainline-v6.11-rc1 commit 6463e5e41842c58da06ce4a0ff1b5bb923f5f033 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... -------------------------------- Extend Intel's check on MSR_TSC_AUX[63:32] to all vCPU models that are Intel compatible, i.e. aren't AMD or Hygon in KVM's world, as the behavior is architectural, i.e. applies to any CPU that is compatible with Intel's architecture. Applying the behavior strictly to Intel wasn't intentional, KVM simply didn't have a concept of "Intel compatible" as of commit 61a05d444d2c ("KVM: x86: Tie Intel and AMD behavior for MSR_TSC_AUX to guest CPU model"). Link: https://lore.kernel.org/r/20240405235603.1173076-5-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Lin Yujun <linyujun809@h-partners.com> --- arch/x86/kvm/x86.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 8b0af52b60ff..de44bd217b26 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -1932,11 +1932,11 @@ static int __kvm_set_msr(struct kvm_vcpu *vcpu, u32 index, u64 data, * incomplete and conflicting architectural behavior. Current * AMD CPUs completely ignore bits 63:32, i.e. they aren't * reserved and always read as zeros. Enforce Intel's reserved - * bits check if and only if the guest CPU is Intel, and clear - * the bits in all other cases. This ensures cross-vendor - * migration will provide consistent behavior for the guest. + * bits check if the guest CPU is Intel compatible, otherwise + * clear the bits. This ensures cross-vendor migration will + * provide consistent behavior for the guest. */ - if (guest_cpuid_is_intel(vcpu) && (data >> 32) != 0) + if (guest_cpuid_is_intel_compatible(vcpu) && (data >> 32) != 0) return 1; data = (u32)data; -- 2.34.1