From mboxrd@z Thu Jan  1 00:00:00 1970
From: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Subject: Re: [PATCH v3 5/9] KVM: MMU: introduce SPTE_WRITE_PROTECT bit
Date: Tue, 24 Apr 2012 11:34:31 +0800
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Cc: Xiao Guangrong <xiaoguangrong.eric@gmail.com>,
	Avi Kivity <avi@redhat.com>,
	LKML <linux-kernel@vger.kernel.org>, KVM <kvm@vger.kernel.org>
To: Marcelo Tosatti <mtosatti@redhat.com>
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On 04/24/2012 08:45 AM, Marcelo Tosatti wrote:


>> I think it is not too hard to check. :)
> 
> You are minimizing the possible impact these modifications have.
> 
> Perhaps you should prepare code under mmu_lock to handle concurrent spte
> R->W updates first, and then later introduce the concurrent updates. In
> a way that its clear for somebody reading the code that parallel updates
> can happen (say read spte once, work on local copy, later re-read spte).
> 


Good idea. I will refine it in the next version. Thank you, Marcelo! :)