When a guest issues a cpuid instruction for Fn0000000D_x0B_{x00,x01}, KVM will be intercepting the CPUID instruction and will need to access the guest MSR_IA32_XSS value. For SEV-ES, the XSS value is encrypted and needs to be included in the GHCB to be visible to the hypervisor. Signed-off-by: John Allen --- v2: - Omit passing through XSS as this has already been properly implemented in a26b7cd22546 ("KVM: SEV: Do not intercept accesses to MSR_IA32_XSS for SEV-ES guests") v3: - Move guest kernel GHCB_ACCESSORS definition to new series. v4: - Change logic structure to be more intuitive. --- arch/x86/kvm/svm/sev.c | 5 +++++ arch/x86/kvm/svm/svm.h | 1 + 2 files changed, 6 insertions(+) diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c index f4381878a9e5..33c42dd853b3 100644 --- a/arch/x86/kvm/svm/sev.c +++ b/arch/x86/kvm/svm/sev.c @@ -3310,6 +3310,11 @@ static void sev_es_sync_from_ghcb(struct vcpu_svm *svm) vcpu->arch.cpuid_dynamic_bits_dirty = true; } + if (kvm_ghcb_xss_is_valid(svm)) { + vcpu->arch.ia32_xss = ghcb_get_xss(ghcb); + vcpu->arch.cpuid_dynamic_bits_dirty = true; + } + /* Copy the GHCB exit information into the VMCB fields */ exit_code = ghcb_get_sw_exit_code(ghcb); control->exit_code = lower_32_bits(exit_code); diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h index 3c7f208b7935..552c58b050f1 100644 --- a/arch/x86/kvm/svm/svm.h +++ b/arch/x86/kvm/svm/svm.h @@ -935,5 +935,6 @@ DEFINE_KVM_GHCB_ACCESSORS(sw_exit_info_1) DEFINE_KVM_GHCB_ACCESSORS(sw_exit_info_2) DEFINE_KVM_GHCB_ACCESSORS(sw_scratch) DEFINE_KVM_GHCB_ACCESSORS(xcr0) +DEFINE_KVM_GHCB_ACCESSORS(xss) #endif -- 2.47.3