Re: [PATCH] KVM: SVM: Assume a 64-bit hypercall for guests with protected state

[Paolo Bonzini]

On 24/05/21 15:58, Tom Lendacky wrote:
> > Would it hurt if we just move 'vcpu->arch.guest_state_protected' check
> > to is_64_bit_mode() itself? It seems to be too easy to miss this
> > peculiar detail about SEV in review if new is_64_bit_mode() users are to
> > be added.
> I thought about that, but wondered if is_64_bit_mode() was to be used in
> other places in the future, if it would be a concern. I think it would be
> safe since anyone adding it to a new section of code is likely to look at
> what that function is doing first.
>
> I'm ok with this. Paolo, I know you already queued this, but would you
> prefer moving the check into is_64_bit_mode()?

Let's introduce a new wrapper is_64_bit_hypercall, and add a 
WARN_ON_ONCE(vcpu->arch.guest_state_protected) to is_64_bit_mode.

Paolo