From mboxrd@z Thu Jan  1 00:00:00 1970
From: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Subject: Re: [PATCH 1/4] KVM: MMU: don't drop spte if overwrite it from W
 to RO
Date: Mon, 15 Nov 2010 13:34:24 +0800
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Cc: Marcelo Tosatti <mtosatti@redhat.com>,
	LKML <linux-kernel@vger.kernel.org>, KVM <kvm@vger.kernel.org>
To: Avi Kivity <avi@redhat.com>
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On 11/14/2010 06:52 PM, Avi Kivity wrote:
> On 11/12/2010 12:30 PM, Xiao Guangrong wrote:
>> We just need flush tlb if overwrite a writable spte with a read-only one
>>
> 
> What are the advantages?  Avoid playing with rmap, and avoid a window
> where the spte is missing?
> 

Both, but only the first was in my mind when i'm making the patch :-)