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Subject: Re: [PATCH 21/24] KVM: x86/mmu: Tweak auditing WARN for A/D bits to
 !PRESENT (was MMIO)
To:     Matteo Croce <mcroce@linux.microsoft.com>,
        Sean Christopherson <seanjc@google.com>
Cc:     Vitaly Kuznetsov <vkuznets@redhat.com>,
        Wanpeng Li <wanpengli@tencent.com>,
        Jim Mattson <jmattson@google.com>,
        Joerg Roedel <joro@8bytes.org>, kvm@vger.kernel.org,
        linux-kernel@vger.kernel.org, Ben Gardon <bgardon@google.com>
References: <20210225204749.1512652-1-seanjc@google.com>
 <20210225204749.1512652-22-seanjc@google.com>
 <20210507010518.26aa74f0@linux.microsoft.com>
From:   Paolo Bonzini <pbonzini@redhat.com>
Message-ID: <3c33b99f-7a8c-a897-9c3e-d5e71d1e2e25@redhat.com>
Date:   Fri, 7 May 2021 09:38:31 +0200
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On 07/05/21 01:05, Matteo Croce wrote:
> On Thu, 25 Feb 2021 12:47:46 -0800
> Sean Christopherson <seanjc@google.com> wrote:
> 
>> Tweak the MMU_WARN that guards against weirdness when querying A/D
>> status to fire on a !MMU_PRESENT SPTE, as opposed to a MMIO SPTE.
>> Attempting to query A/D status on any kind of !MMU_PRESENT SPTE, MMIO
>> or otherwise, indicates a KVM bug.  Case in point, several now-fixed
>> bugs were identified by enabling this new WARN.
>>
>> Signed-off-by: Sean Christopherson <seanjc@google.com>
> 
> You made the 1.000.000th commit, congrats!
> 
> $ git log --oneline --reverse |sed '1000000!d'
> 8f366ae6d8c5 KVM: x86/mmu: Tweak auditing WARN for A/D bits to !PRESENT (was MMIO)

????????????

Paolo