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Date:   Thu, 28 Apr 2022 14:33:10 +0000
From:   Sean Christopherson <seanjc@google.com>
To:     Lai Jiangshan <jiangshanlai@gmail.com>
Cc:     Paolo Bonzini <pbonzini@redhat.com>,
        Vitaly Kuznetsov <vkuznets@redhat.com>,
        Wanpeng Li <wanpengli@tencent.com>,
        Jim Mattson <jmattson@google.com>,
        Joerg Roedel <joro@8bytes.org>, kvm@vger.kernel.org,
        LKML <linux-kernel@vger.kernel.org>,
        David Woodhouse <dwmw@amazon.co.uk>,
        Mingwei Zhang <mizhang@google.com>,
        Maxim Levitsky <mlevitsk@redhat.com>
Subject: Re: [PATCH v2 6/8] KVM: Fix multiple races in gfn=>pfn cache refresh
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On Thu, Apr 28, 2022, Lai Jiangshan wrote:
> On Wed, Apr 27, 2022 at 7:16 PM Sean Christopherson <seanjc@google.com> wrote:
> 
> > @@ -159,10 +249,23 @@ int kvm_gfn_to_pfn_cache_refresh(struct kvm *kvm, struct gfn_to_pfn_cache *gpc,
> >
> 
> The following code of refresh_in_progress is somewhat like mutex.
> 
> + mutex_lock(&gpc->refresh_in_progress); // before write_lock_irq(&gpc->lock);
> 
> Is it fit for the intention?

Yeah, I mutex should work.  Not sure why I shied away from a mutex...