[v1] SVM guest shadow stack support

[PATCH 8/9] KVM: SVM: Use KVM-governed features to track SHSTK

Posted by John Allen 2 years, 4 months ago

Use the KVM-governed features framework to track whether SHSTK can be by
both userspace and guest for SVM.

Signed-off-by: John Allen <john.allen@amd.com>
---
 arch/x86/kvm/svm/svm.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index ee7c7d0a09ab..00a8cef3cbb8 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -4366,6 +4366,7 @@ static void svm_vcpu_after_set_cpuid(struct kvm_vcpu *vcpu)
 	kvm_governed_feature_check_and_set(vcpu, X86_FEATURE_PFTHRESHOLD);
 	kvm_governed_feature_check_and_set(vcpu, X86_FEATURE_VGIF);
 	kvm_governed_feature_check_and_set(vcpu, X86_FEATURE_VNMI);
+	kvm_governed_feature_check_and_set(vcpu, X86_FEATURE_SHSTK);
 
 	svm_recalc_instruction_intercepts(vcpu, svm);
 
-- 
2.40.1

Re: [PATCH 8/9] KVM: SVM: Use KVM-governed features to track SHSTK

Posted by Maxim Levitsky 2 years, 3 months ago

On Tue, 2023-10-10 at 20:02 +0000, John Allen wrote:
> Use the KVM-governed features framework to track whether SHSTK can be by
> both userspace and guest for SVM.
> 
> Signed-off-by: John Allen <john.allen@amd.com>
> ---
>  arch/x86/kvm/svm/svm.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
> index ee7c7d0a09ab..00a8cef3cbb8 100644
> --- a/arch/x86/kvm/svm/svm.c
> +++ b/arch/x86/kvm/svm/svm.c
> @@ -4366,6 +4366,7 @@ static void svm_vcpu_after_set_cpuid(struct kvm_vcpu *vcpu)
>  	kvm_governed_feature_check_and_set(vcpu, X86_FEATURE_PFTHRESHOLD);
>  	kvm_governed_feature_check_and_set(vcpu, X86_FEATURE_VGIF);
>  	kvm_governed_feature_check_and_set(vcpu, X86_FEATURE_VNMI);
> +	kvm_governed_feature_check_and_set(vcpu, X86_FEATURE_SHSTK);
>  
>  	svm_recalc_instruction_intercepts(vcpu, svm);
>  

Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>

Best regards,
	Maxim Levitsky