Re: [PATCH] KVM: VMX: Flush shadow VMCS on emergency reboot

[Xiaoyao Li]

On 4/12/2025 12:57 AM, Sean Christopherson wrote:
> > If a VMM wants to leverage the VMXOFF behavior, software enumeration
> > might be needed for nested virtualization. Using CPU F/M/S (SPR+) to
> > enumerate a behavior could be problematic for virtualization. Right?
> Yeah, F/M/S is a bad idea.  Architecturally, I think the behavior needs to be
> tied to support for SEAM.  Is there a safe-ish way to probe for SEAM support,
> without having to glean it from MSR_IA32_MKTME_KEYID_PARTITIONING?

yes, the bit 15 of MSR_IA32_MTRRCAP.