KVM: x86: Use KVM-governed feature framework to track "LAM enabled"

Upstream commit: 183bdd1 Conflict: none Use the governed feature framework to track if Linear Address Masking (LAM) is "enabled", i.e. if LAM can be used by the guest. Using the framework to avoid the relative expensive call guest_cpuid_has() during cr3 and vmexit handling paths for LAM. No functional change intended. Intel-SIG: commit 183bdd1 KVM: x86: Use KVM-governed feature framework to track "LAM enabled" Backport KVM Linear Address Masking (LAM) support. Signed-off-by: Binbin Wu <[email protected]> Tested-by: Xuelian Guo <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Sean Christopherson <[email protected]> [ Zhiquan Li: amend commit log ] Signed-off-by: Zhiquan Li <[email protected]>
deepin-community · Dec 27, 2024 · 08e842c · 08e842c
1 parent 979f0ff
commit 08e842c
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Showing 4 changed files with 4 additions and 4 deletions.
diff --git a/arch/x86/kvm/cpuid.h b/arch/x86/kvm/cpuid.h
@@ -285,8 +285,7 @@ static __always_inline bool guest_can_use(struct kvm_vcpu *vcpu,
 
 static inline bool kvm_vcpu_is_legal_cr3(struct kvm_vcpu *vcpu, unsigned long cr3)
 {
-	if (kvm_cpu_cap_has(X86_FEATURE_LAM) &&
-	    guest_cpuid_has(vcpu, X86_FEATURE_LAM))
+	if (guest_can_use(vcpu, X86_FEATURE_LAM))
 		cr3 &= ~(X86_CR3_LAM_U48 | X86_CR3_LAM_U57);
 
 	return kvm_vcpu_is_legal_gpa(vcpu, cr3);

diff --git a/arch/x86/kvm/governed_features.h b/arch/x86/kvm/governed_features.h
@@ -16,6 +16,7 @@ KVM_GOVERNED_X86_FEATURE(PAUSEFILTER)
 KVM_GOVERNED_X86_FEATURE(PFTHRESHOLD)
 KVM_GOVERNED_X86_FEATURE(VGIF)
 KVM_GOVERNED_X86_FEATURE(VNMI)
+KVM_GOVERNED_X86_FEATURE(LAM)
 
 #undef KVM_GOVERNED_X86_FEATURE
 #undef KVM_GOVERNED_FEATURE
diff --git a/arch/x86/kvm/mmu.h b/arch/x86/kvm/mmu.h
@@ -148,8 +148,7 @@ static inline unsigned long kvm_get_active_pcid(struct kvm_vcpu *vcpu)
 
 static inline unsigned long kvm_get_active_cr3_lam_bits(struct kvm_vcpu *vcpu)
 {
-	if (!kvm_cpu_cap_has(X86_FEATURE_LAM) ||
-	    !guest_cpuid_has(vcpu, X86_FEATURE_LAM))
+	if (!guest_can_use(vcpu, X86_FEATURE_LAM))
 		return 0;
 
 	return kvm_read_cr3(vcpu) & (X86_CR3_LAM_U48 | X86_CR3_LAM_U57);

diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
@@ -7842,6 +7842,7 @@ static void vmx_vcpu_after_set_cpuid(struct kvm_vcpu *vcpu)
 		kvm_governed_feature_check_and_set(vcpu, X86_FEATURE_XSAVES);
 
 	kvm_governed_feature_check_and_set(vcpu, X86_FEATURE_VMX);
+	kvm_governed_feature_check_and_set(vcpu, X86_FEATURE_LAM);
 
 	vmx_setup_uret_msrs(vmx);