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Message-ID: <1abaea0d-7e21-b596-eb5d-75217133a504@intel.com>
Date:   Tue, 7 Jun 2022 23:00:51 +0800
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Subject: Re: [PATCH v2] KVM: x86/mmu: Check every prev_roots in
 __kvm_mmu_free_obsolete_roots()
Content-Language: en-US
To:     Sean Christopherson <seanjc@google.com>
CC:     <pbonzini@redhat.com>, Vitaly Kuznetsov <vkuznets@redhat.com>,
        Wanpeng Li <wanpengli@tencent.com>,
        Jim Mattson <jmattson@google.com>,
        Joerg Roedel <joro@8bytes.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        Dave Hansen <dave.hansen@linux.intel.com>, <x86@kernel.org>,
        "H. Peter Anvin" <hpa@zytor.com>, Ben Gardon <bgardon@google.com>,
        <kvm@vger.kernel.org>, <linux-kernel@vger.kernel.org>
References: <20220607005905.2933378-1-shaoqin.huang@intel.com>
 <Yp4x0twziuEr3KRm@google.com>
From:   "Huang, Shaoqin" <shaoqin.huang@intel.com>
In-Reply-To: <Yp4x0twziuEr3KRm@google.com>
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Thanks Sean!

On 6/7/2022 12:56 AM, Sean Christopherson wrote:
> On Mon, Jun 06, 2022, shaoqin.huang@intel.com wrote:
>> From: Shaoqin Huang <shaoqin.huang@intel.com>
>>
>> When freeing obsolete previous roots, check prev_roots as intended, not
>> the current root.
>>
>> Signed-off-by: Shaoqin Huang <shaoqin.huang@intel.com>
>> Fixes: 527d5cd7eece ("KVM: x86/mmu: Zap only obsolete roots if a root shadow page is zapped")
> 
> Because KVM patches aren't guaranteed to be backported without it (though it's
> "only" v5.18 that's affected), this needs:
> 
>    Cc: stable@vger.kernel.org
> 
> Reviewed-by: Sean Christopherson <seanjc@google.com>