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Date: Thu, 14 Aug 2014 13:41:43 +0800
From: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
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To: David Matlack <dmatlack@google.com>
CC: gleb@redhat.com, avi.kivity@gmail.com, mtosatti@redhat.com,
        Paolo Bonzini <pbonzini@redhat.com>, linux-kernel@vger.kernel.org,
        kvm@vger.kernel.org, stable@vger.kernel.org
Subject: Re: [PATCH 1/2] KVM: fix cache stale memslot info with correct mmio
 generation number
References: <1407819721-27833-1-git-send-email-xiaoguangrong@linux.vnet.ibm.com> <CALzav=eZyM4_Y6yVoDnTZZUEbbF+T8WR_mSZa3h51FHs1uGBWQ@mail.gmail.com>
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On 08/13/2014 05:18 AM, David Matlack wrote:
> On Mon, Aug 11, 2014 at 10:02 PM, Xiao Guangrong
> <xiaoguangrong@linux.vnet.ibm.com> wrote:
>> @@ -722,9 +719,10 @@ static struct kvm_memslots *install_new_memslots(struct kvm *kvm,
>>  {
>>         struct kvm_memslots *old_memslots = kvm->memslots;
>>
> 
> I think you want
> 
>   slots->generation = old_memslots->generation;
> 
> here.
> 
> On the KVM_MR_DELETE path, install_new_memslots is called twice so this
> patch introduces a short window of time where the generation number
> actually decreases.

Yes, indeed. Thank you for pointing it out, will update.