Re: [PATCH v7 03/26] x86/fpu/xstate: Add CET supervisor mode state support

[Yang, Weijiang]

On 11/24/2023 5:45 PM, Peter Zijlstra wrote:
> On Fri, Nov 24, 2023 at 12:53:07AM -0500, Yang Weijiang wrote:
>
> > Note, in KVM case, guest CET supervisor state i.e., IA32_PL{0,1,2}_MSRs,
> > are preserved after VM-Exit until host/guest fpstates are swapped, but
> > since host supervisor shadow stack is disabled, the preserved MSRs won't
> > hurt host.
> Just to be clear, with FRED all this changes, right? Then we get more
> VMCS fields for SSS state.

Yes, I think so, KVM needs to properly handle guest SSS state and host FRED states.

Thanks!