Allow userspace to set the flag in kvm_sev_init.flags. KVM still needs to set the flag for backwards compatibility, but disallowing SVM_SEV_FEAT_SNP_ACTIVE for an SNP guest is "bizarre." Suggested-by: Sean Christopherson Cc: Borislav Petkov (AMD) Link: https://lore.kernel.org/kvm/aaWog_UjW-M3412C@google.com/ Signed-off-by: Kim Phillips --- v3: new arch/x86/include/asm/svm.h | 3 ++- arch/x86/kvm/svm/sev.c | 8 ++++++-- 2 files changed, 8 insertions(+), 3 deletions(-) diff --git a/arch/x86/include/asm/svm.h b/arch/x86/include/asm/svm.h index 7e3f9d92351a..4f844a72890c 100644 --- a/arch/x86/include/asm/svm.h +++ b/arch/x86/include/asm/svm.h @@ -307,7 +307,8 @@ static_assert((X2AVIC_4K_MAX_PHYSICAL_ID & AVIC_PHYSICAL_MAX_INDEX_MASK) == X2AV #define SVM_SEV_FEAT_DEBUG_SWAP BIT(5) #define SVM_SEV_FEAT_SECURE_TSC BIT(9) -#define SVM_SEV_FEAT_SNP_ONLY_MASK SVM_SEV_FEAT_SECURE_TSC +#define SVM_SEV_FEAT_SNP_ONLY_MASK (SVM_SEV_FEAT_SNP_ACTIVE | \ + SVM_SEV_FEAT_SECURE_TSC) #define VMCB_ALLOWED_SEV_FEATURES_VALID BIT_ULL(63) diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c index 2b4f3c05e282..9663424c0cf0 100644 --- a/arch/x86/kvm/svm/sev.c +++ b/arch/x86/kvm/svm/sev.c @@ -3165,8 +3165,12 @@ void __init sev_hardware_setup(void) cpu_feature_enabled(X86_FEATURE_NO_NESTED_DATA_BP)) sev_supported_vmsa_features |= SVM_SEV_FEAT_DEBUG_SWAP; - if (sev_snp_enabled && tsc_khz && cpu_feature_enabled(X86_FEATURE_SNP_SECURE_TSC)) - sev_supported_vmsa_features |= SVM_SEV_FEAT_SECURE_TSC; + if (sev_snp_enabled) { + sev_supported_vmsa_features |= SVM_SEV_FEAT_SNP_ACTIVE; + + if (tsc_khz && cpu_feature_enabled(X86_FEATURE_SNP_SECURE_TSC)) + sev_supported_vmsa_features |= SVM_SEV_FEAT_SECURE_TSC; + } } void sev_hardware_unsetup(void) -- 2.43.0