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Date:   Thu, 6 Jan 2022 22:48:10 +0000
From:   Sean Christopherson <seanjc@google.com>
To:     David Matlack <dmatlack@google.com>
Cc:     Peter Xu <peterx@redhat.com>, Paolo Bonzini <pbonzini@redhat.com>,
        kvm list <kvm@vger.kernel.org>,
        Ben Gardon <bgardon@google.com>,
        Joerg Roedel <joro@8bytes.org>,
        Jim Mattson <jmattson@google.com>,
        Wanpeng Li <wanpengli@tencent.com>,
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        Oliver Upton <oupton@google.com>,
        Harish Barathvajasankar <hbarath@google.com>,
        Peter Shier <pshier@google.com>,
        "Nikunj A . Dadhania" <nikunj@amd.com>
Subject: Re: [PATCH v1 09/13] KVM: x86/mmu: Split huge pages when dirty
 logging is enabled
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References: <20211213225918.672507-1-dmatlack@google.com>
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On Wed, Jan 05, 2022, David Matlack wrote:
> > I don't even see anywhere that the tdp mmu disables the EXEC bit for 4K.. if
> > that's true then perhaps we can even drop "access" and this check?  But I could
> > have missed something.
> 
> TDP MMU always passes ACC_ALL so the access check could be omitted
> from this patch. But it will be needed to support eager splitting for
> the shadow MMU, which does not always allow execution.

Sure, but let's add that complexity when it's needed.  That also has the advantage
of documenting, in git history, why the param is in needed.