On Thu, 29 May 2025 16:17:58 -0500, Tom Lendacky wrote:
> This series removes some guest policy checks that can be better controlled
> by the SEV firmware.
>
> - Remove the check for the SMT policy bit. Currently, a check is made to
> ensure the SMT policy bit is set to 1. However, there is no reason for
> KVM to do this. The SMT policy bit, when 0, is used to ensure that SMT
> has been disabled *in the BIOS.* As this does not require any special
> support within KVM, the check can be safely removed to allow the SEV
> firmware to determine whether the system meets the policy.
>
> [...]
Applied to kvm-x86 svm. FWIW, I'm not entirely sure I love the idea of doing
nothing, e.g. it'd be nice to enumerate support to userspace. But adding a
bunch of code to regurgitate information that's likely available to userspace
(or more likely, the platform admin/orchestrator) doesn't seem worthwile either.
I'll make sure to flag this for Paolo's eyeballs.
[1/2] KVM: SVM: Allow SNP guest policy disallow running with SMT enabled
https://github.com/kvm-x86/linux/commit/9f4701e05fae
[2/2] KVM: SVM: Allow SNP guest policy to specify SINGLE_SOCKET
https://github.com/kvm-x86/linux/commit/24be2b7956a5
--
https://github.com/kvm-x86/kvm-unit-tests/tree/next
