From: "Borislav Petkov (AMD)" bp@alien8.de
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 jinpu.wang@ionos.com Signed-off-by: Jinpu Wang jinpu.wang@ionos.com Signed-off-by: Borislav Petkov (AMD) bp@alien8.de --- arch/x86/kvm/cpuid.c | 4 ++++ 1 file changed, 4 insertions(+)
diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index 02196db26a08..8f587c5bb6bc 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -822,6 +822,7 @@ void kvm_set_cpu_caps(void) kvm_cpu_cap_check_and_set(X86_FEATURE_SBPB); kvm_cpu_cap_check_and_set(X86_FEATURE_IBPB_BRTYPE); kvm_cpu_cap_check_and_set(X86_FEATURE_SRSO_NO); + kvm_cpu_cap_check_and_set(X86_FEATURE_VERW_CLEAR);
kvm_cpu_cap_init_kvm_defined(CPUID_8000_0022_EAX, F(PERFMON_V2) @@ -831,6 +832,9 @@ void kvm_set_cpu_caps(void) 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); + /* * Synthesize "LFENCE is serializing" into the AMD-defined entry in * KVM's supported CPUID if the feature is reported as supported by the