If kvm supports shadow stack, pass through shadow stack MSRs to improve
guest performance.
Signed-off-by: John Allen <john.allen@xxxxxxx>
---
arch/x86/kvm/svm/svm.c | 12 ++++++++++++
1 file changed, 12 insertions(+)
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index a027d3c37181..82cde3578c96 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -838,6 +838,18 @@ static void svm_recalc_msr_intercepts(struct kvm_vcpu *vcpu)
svm_set_intercept_for_msr(vcpu, MSR_IA32_SYSENTER_ESP, MSR_TYPE_RW,
guest_cpuid_is_intel_compatible(vcpu));
+ if (kvm_cpu_cap_has(X86_FEATURE_SHSTK)) {
+ bool shstk_enabled = guest_cpu_cap_has(vcpu, X86_FEATURE_SHSTK);
+
+ svm_set_intercept_for_msr(vcpu, MSR_IA32_U_CET, MSR_TYPE_RW, !shstk_enabled);
+ svm_set_intercept_for_msr(vcpu, MSR_IA32_S_CET, MSR_TYPE_RW, !shstk_enabled);
+ svm_set_intercept_for_msr(vcpu, MSR_IA32_PL0_SSP, MSR_TYPE_RW, !shstk_enabled);
+ svm_set_intercept_for_msr(vcpu, MSR_IA32_PL1_SSP, MSR_TYPE_RW, !shstk_enabled);
+ svm_set_intercept_for_msr(vcpu, MSR_IA32_PL2_SSP, MSR_TYPE_RW, !shstk_enabled);
+ svm_set_intercept_for_msr(vcpu, MSR_IA32_PL3_SSP, MSR_TYPE_RW, !shstk_enabled);
+ svm_set_intercept_for_msr(vcpu, MSR_IA32_INT_SSP_TAB, MSR_TYPE_RW, !shstk_enabled);
+ }
+
if (sev_es_guest(vcpu->kvm))
sev_es_recalc_msr_intercepts(vcpu);
--
2.34.1
