Re: [PATCH 24/28] KVM: x86/mmu: hard code more bits in kvm_init_shadow_npt_mmu

Sean Christopherson
2026-05-01T13:29:59Z

On Fri, May 01, 2026, Paolo Bonzini wrote:
> On Thu, Apr 30, 2026 at 9:09 PM Sean Christopherson <seanjc@google.com> wrote:
> >
> > On Thu, Apr 30, 2026, Paolo Bonzini wrote:
> > > Likewise, clear X86_CR4_SMAP to avoid that KVM erroneously faults on
> > > supervisor accesses to an U=1 page.
> >
> > What, don't you want to more closely follow real hardware? :-D
>
> Uh, I cannot parse this. Is there an errata I don't know about?

Errata 1096, where the decode assist fails because the CPU tries to read the code
stream with data reads and trips SMAP. Not a truly spurious fault since it's not
software visible, but I couldn't resist the joke :-)