| Message ID | aa46606f21303d5b45544ed2043966c2b3d7f69a.1694811272.git.thomas.lendacky@amd.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | SEV-ES TSC_AUX virtualization fix and optimization | expand |
On 9/15/23 15:54, Tom Lendacky wrote: > With the TSC_AUX virtualization support now in the vcpu_set_after_cpuid() > path, the intercepts must be either cleared or set based on the guest > CPUID input. Currently the support only clears the intercepts. > > Also, vcpu_set_after_cpuid() calls svm_recalc_instruction_intercepts() as > part of the processing, so the setting or clearing of the RDTSCP intercept > can be dropped from the TSC_AUX virtualization support. > > Update the support to always set or clear the TSC_AUX MSR intercept based > on the virtualization requirements. > > Fixes: 296d5a17e793 ("KVM: SEV-ES: Use V_TSC_AUX if available instead of RDTSC/MSR_TSC_AUX intercepts") > Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> In the end, I was really on the fence about this being a separate patch given the common Fixes: tag. Your call, feel free to squash with patch #1 and massage the commit message if you'd like (or I can send a v3 with them squashed if you prefer). Thanks, Tom > --- > arch/x86/kvm/svm/sev.c | 11 +++++------ > 1 file changed, 5 insertions(+), 6 deletions(-) > > diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c > index 4ac01f338903..4900c078045a 100644 > --- a/arch/x86/kvm/svm/sev.c > +++ b/arch/x86/kvm/svm/sev.c > @@ -2966,12 +2966,11 @@ static void sev_es_vcpu_after_set_cpuid(struct vcpu_svm *svm) > { > struct kvm_vcpu *vcpu = &svm->vcpu; > > - if (boot_cpu_has(X86_FEATURE_V_TSC_AUX) && > - (guest_cpuid_has(vcpu, X86_FEATURE_RDTSCP) || > - guest_cpuid_has(vcpu, X86_FEATURE_RDPID))) { > - set_msr_interception(vcpu, svm->msrpm, MSR_TSC_AUX, 1, 1); > - if (guest_cpuid_has(vcpu, X86_FEATURE_RDTSCP)) > - svm_clr_intercept(svm, INTERCEPT_RDTSCP); > + if (boot_cpu_has(X86_FEATURE_V_TSC_AUX)) { > + bool v_tsc_aux = guest_cpuid_has(vcpu, X86_FEATURE_RDTSCP) || > + guest_cpuid_has(vcpu, X86_FEATURE_RDPID); > + > + set_msr_interception(vcpu, svm->msrpm, MSR_TSC_AUX, v_tsc_aux, v_tsc_aux); > } > } >
diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c index 4ac01f338903..4900c078045a 100644 --- a/arch/x86/kvm/svm/sev.c +++ b/arch/x86/kvm/svm/sev.c @@ -2966,12 +2966,11 @@ static void sev_es_vcpu_after_set_cpuid(struct vcpu_svm *svm) { struct kvm_vcpu *vcpu = &svm->vcpu; - if (boot_cpu_has(X86_FEATURE_V_TSC_AUX) && - (guest_cpuid_has(vcpu, X86_FEATURE_RDTSCP) || - guest_cpuid_has(vcpu, X86_FEATURE_RDPID))) { - set_msr_interception(vcpu, svm->msrpm, MSR_TSC_AUX, 1, 1); - if (guest_cpuid_has(vcpu, X86_FEATURE_RDTSCP)) - svm_clr_intercept(svm, INTERCEPT_RDTSCP); + if (boot_cpu_has(X86_FEATURE_V_TSC_AUX)) { + bool v_tsc_aux = guest_cpuid_has(vcpu, X86_FEATURE_RDTSCP) || + guest_cpuid_has(vcpu, X86_FEATURE_RDPID); + + set_msr_interception(vcpu, svm->msrpm, MSR_TSC_AUX, v_tsc_aux, v_tsc_aux); } }
With the TSC_AUX virtualization support now in the vcpu_set_after_cpuid() path, the intercepts must be either cleared or set based on the guest CPUID input. Currently the support only clears the intercepts. Also, vcpu_set_after_cpuid() calls svm_recalc_instruction_intercepts() as part of the processing, so the setting or clearing of the RDTSCP intercept can be dropped from the TSC_AUX virtualization support. Update the support to always set or clear the TSC_AUX MSR intercept based on the virtualization requirements. Fixes: 296d5a17e793 ("KVM: SEV-ES: Use V_TSC_AUX if available instead of RDTSC/MSR_TSC_AUX intercepts") Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> --- arch/x86/kvm/svm/sev.c | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-)