Re: [PATCH v3] KVM: SVM: Don't allow L1 intercepts for instructions not advertised

From: Sean Christopherson

Date: Mon Jan 12 2026 - 12:41:34 EST


On Mon, 15 Dec 2025 19:25:10 +0000, Kevin Cheng wrote:
> If a feature is not advertised in the guest's CPUID, prevent L1 from
> intercepting the unsupported instructions by clearing the corresponding
> intercept in KVM's cached vmcb12.
>
> When an L2 guest executes an instruction that is not advertised to L1,
> we expect a #UD exception to be injected by L0. However, the nested svm
> exit handler first checks if the instruction intercept is set in vmcb12,
> and if so, synthesizes an exit from L2 to L1 instead of a #UD exception.
> If a feature is not advertised, the L1 intercept should be ignored.
>
> [...]

Applied to kvm-x86 svm, thanks!

[1/1] KVM: SVM: Don't allow L1 intercepts for instructions not advertised
https://github.com/kvm-x86/linux/commit/1d1722e52fcd

--
https://github.com/kvm-x86/linux/tree/next