From 34b87ac4bb903d986a78dc3cd3570e2cb27720bb Mon Sep 17 00:00:00 2001 From: "Borislav Petkov (AMD)" Date: Tue, 9 Sep 2025 20:28:26 -0400 Subject: [PATCH] KVM: SVM: Set synthesized TSA CPUID flags Commit f3f9deccfc68a6b7c8c1cc51e902edba23d309d4 LTS VERW_CLEAR is supposed to be set only by the hypervisor to denote TSA mitigation support to a guest. SQ_NO and L1_NO are both synthesizable, and are going to be set by hw CPUID on future machines. So keep the kvm_cpu_cap_init_kvm_defined() invocation *and* set them when synthesized. This fix is stable-only. Co-developed-by: Jinpu Wang Signed-off-by: Jinpu Wang Signed-off-by: Borislav Petkov (AMD) Signed-off-by: Greg Kroah-Hartman Cc: # 5.15.y Signed-off-by: Boris Ostrovsky Signed-off-by: Greg Kroah-Hartman --- arch/x86/kvm/cpuid.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index 4a644fcb0334..8a72b4bf5901 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -564,10 +564,15 @@ void kvm_set_cpu_caps(void) if (cpu_feature_enabled(X86_FEATURE_SRSO_NO)) kvm_cpu_cap_set(X86_FEATURE_SRSO_NO); + kvm_cpu_cap_check_and_set(X86_FEATURE_VERW_CLEAR); + kvm_cpu_cap_init_kvm_defined(CPUID_8000_0021_ECX, F(TSA_SQ_NO) | F(TSA_L1_NO) ); + kvm_cpu_cap_check_and_set(X86_FEATURE_TSA_SQ_NO); + kvm_cpu_cap_check_and_set(X86_FEATURE_TSA_L1_NO); + /* * Hide RDTSCP and RDPID if either feature is reported as supported but * probing MSR_TSC_AUX failed. This is purely a sanity check and