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From:   Mingwei Zhang <mizhang@google.com>
Date:   Tue, 6 Jun 2023 15:48:21 -0700
Message-ID: <CAL715WKHLzpnHF+HZH_8fNkUMfHYGHAOQacUNRR0b6-WpUuFMA@mail.gmail.com>
Subject: Re: [PATCH] KVM: x86/mmu: Remove KVM MMU write lock when accessing indirect_shadow_pages
To:     Sean Christopherson <seanjc@google.com>
Cc:     Jim Mattson <jmattson@google.com>,
        Paolo Bonzini <pbonzini@redhat.com>,
        "H. Peter Anvin" <hpa@zytor.com>, kvm@vger.kernel.org,
        linux-kernel@vger.kernel.org, Ben Gardon <bgardon@google.com>
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> >
> > So I think this?
>
> Hmm. I agree with both points above, but below, the change seems too
> heavyweight. smp_wb() is a mfence(), i.e., serializing all
> loads/stores before the instruction. Doing that for every shadow page
> creation and destruction seems a lot.
>
typo: smp_wb() => smp_mb().