[PATCH 08/12] KVM: nSVM: Use KVM-governed feature framework to track "vVM{SAVE,LOAD} enabled"

From: Sean Christopherson
Date: Fri Feb 17 2023 - 18:11:19 EST


Track "virtual VMSAVE/VMLOAD exposed to L1" via a governed feature flag
instead of using a dedicated bit/flag in vcpu_svm.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
---
arch/x86/kvm/governed_features.h | 1 +
arch/x86/kvm/svm/nested.c | 2 +-
arch/x86/kvm/svm/svm.c | 5 ++---
arch/x86/kvm/svm/svm.h | 1 -
4 files changed, 4 insertions(+), 5 deletions(-)

diff --git a/arch/x86/kvm/governed_features.h b/arch/x86/kvm/governed_features.h
index 0335576a80a8..b66b9d550f33 100644
--- a/arch/x86/kvm/governed_features.h
+++ b/arch/x86/kvm/governed_features.h
@@ -9,6 +9,7 @@ KVM_GOVERNED_X86_FEATURE(GBPAGES)
KVM_GOVERNED_X86_FEATURE(XSAVES)
KVM_GOVERNED_X86_FEATURE(NRIPS)
KVM_GOVERNED_X86_FEATURE(TSCRATEMSR)
+KVM_GOVERNED_X86_FEATURE(V_VMSAVE_VMLOAD)

#undef KVM_GOVERNED_X86_FEATURE
#undef KVM_GOVERNED_FEATURE
diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c
index 30e00c4e07c7..6a96058c0e48 100644
--- a/arch/x86/kvm/svm/nested.c
+++ b/arch/x86/kvm/svm/nested.c
@@ -107,7 +107,7 @@ static void nested_svm_uninit_mmu_context(struct kvm_vcpu *vcpu)

static bool nested_vmcb_needs_vls_intercept(struct vcpu_svm *svm)
{
- if (!svm->v_vmload_vmsave_enabled)
+ if (!guest_can_use(&svm->vcpu, X86_FEATURE_V_VMSAVE_VMLOAD))
return true;

if (!nested_npt_enabled(svm))
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index dd4aead5462c..b3f0271c73b9 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -1162,8 +1162,6 @@ static inline void init_vmcb_after_set_cpuid(struct kvm_vcpu *vcpu)

set_msr_interception(vcpu, svm->msrpm, MSR_IA32_SYSENTER_EIP, 0, 0);
set_msr_interception(vcpu, svm->msrpm, MSR_IA32_SYSENTER_ESP, 0, 0);
-
- svm->v_vmload_vmsave_enabled = false;
} else {
/*
* If hardware supports Virtual VMLOAD VMSAVE then enable it
@@ -4153,7 +4151,8 @@ static void svm_vcpu_after_set_cpuid(struct kvm_vcpu *vcpu)

svm->lbrv_enabled = lbrv && guest_cpuid_has(vcpu, X86_FEATURE_LBRV);

- svm->v_vmload_vmsave_enabled = vls && guest_cpuid_has(vcpu, X86_FEATURE_V_VMSAVE_VMLOAD);
+ if (vls && !guest_cpuid_is_intel(vcpu))
+ kvm_governed_feature_check_and_set(vcpu, X86_FEATURE_V_VMSAVE_VMLOAD);

svm->pause_filter_enabled = kvm_cpu_cap_has(X86_FEATURE_PAUSEFILTER) &&
guest_cpuid_has(vcpu, X86_FEATURE_PAUSEFILTER);
diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h
index a523cfcdd12e..1e3e7462b1d7 100644
--- a/arch/x86/kvm/svm/svm.h
+++ b/arch/x86/kvm/svm/svm.h
@@ -258,7 +258,6 @@ struct vcpu_svm {
bool soft_int_injected;

/* optional nested SVM features that are enabled for this guest */
- bool v_vmload_vmsave_enabled : 1;
bool lbrv_enabled : 1;
bool pause_filter_enabled : 1;
bool pause_threshold_enabled : 1;
--
2.39.2.637.g21b0678d19-goog