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Date:   Mon, 18 Sep 2023 12:53:22 +0300
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Subject: Re: [PATCH v9 6/6] KVM: x86/mmu: Handle non-refcounted pages
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To:     David Stevens <stevensd@chromium.org>,
        Sean Christopherson <seanjc@google.com>
Cc:     Yu Zhang <yu.c.zhang@linux.intel.com>,
        Isaku Yamahata <isaku.yamahata@gmail.com>,
        Zhi Wang <zhi.wang.linux@gmail.com>, kvmarm@lists.linux.dev,
        linux-kernel@vger.kernel.org, kvm@vger.kernel.org
References: <20230911021637.1941096-1-stevensd@google.com>
 <20230911021637.1941096-7-stevensd@google.com>
From:   Dmitry Osipenko <dmitry.osipenko@collabora.com>
In-Reply-To: <20230911021637.1941096-7-stevensd@google.com>
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On 9/11/23 05:16, David Stevens wrote:
> --- a/arch/x86/kvm/mmu/paging_tmpl.h
> +++ b/arch/x86/kvm/mmu/paging_tmpl.h
> @@ -848,7 +848,8 @@ static int FNAME(page_fault)(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault
>  
>  out_unlock:
>  	write_unlock(&vcpu->kvm->mmu_lock);
> -	kvm_release_pfn_clean(fault->pfn);
> +	if (fault->is_refcounted_page)
> +		kvm_set_page_accessed(pfn_to_page(fault->pfn));

The other similar occurrences in the code that replaced
kvm_release_pfn_clean() with kvm_set_page_accessed() did it under the
held mmu_lock.

Does kvm_set_page_accessed() needs to be invoked under the lock?

-- 
Best regards,
Dmitry