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    SubjectRe: [PATCH v2 05/25] KVM: x86/mmu: rephrase unclear comment
    On Mon, Feb 21, 2022, Paolo Bonzini wrote:
    > If accessed bits are not supported there simple isn't any distinction
    > between accessed and non-accessed gPTEs, so the comment does not make
    > much sense. Rephrase it in terms of what happens if accessed bits
    > *are* supported.
    >
    > Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
    > ---
    > arch/x86/kvm/mmu/paging_tmpl.h | 2 +-
    > 1 file changed, 1 insertion(+), 1 deletion(-)
    >
    > diff --git a/arch/x86/kvm/mmu/paging_tmpl.h b/arch/x86/kvm/mmu/paging_tmpl.h
    > index 80b4b291002a..d1d17d28e81b 100644
    > --- a/arch/x86/kvm/mmu/paging_tmpl.h
    > +++ b/arch/x86/kvm/mmu/paging_tmpl.h
    > @@ -193,7 +193,7 @@ static bool FNAME(prefetch_invalid_gpte)(struct kvm_vcpu *vcpu,
    > if (!FNAME(is_present_gpte)(gpte))
    > goto no_present;
    >
    > - /* if accessed bit is not supported prefetch non accessed gpte */
    > + /* if accessed bit is supported, prefetch only accessed gpte */

    Can we just reword the whole thing? A/D bits being disabled is the anomaly,
    leading with the "if" makes the logic we really care about seem like a secondary
    concern. E.g.

    /* Prefetch only accessed entries (unless A/D bits are disabled). */

    > if (PT_HAVE_ACCESSED_DIRTY(vcpu->arch.mmu) &&
    > !(gpte & PT_GUEST_ACCESSED_MASK))
    > goto no_present;
    > --
    > 2.31.1
    >
    >

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