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Date: Fri, 13 Apr 2012 18:26:52 +0800
From: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
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To: Marcelo Tosatti <mtosatti@redhat.com>
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Subject: Re: [PATCH 08/13] KVM: MMU: fask check whether page is writable
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On 04/13/2012 07:08 AM, Marcelo Tosatti wrote:


>> Yes, it is used as a cache for mmu_need_write_protect.
>>
>> When the gfn is protected by sync sp or read-only host page we set this bit,
>> and it is be cleared when the sp become unsync or host page becomes writable.
> 
> Wouldnt dropping support for shadow entirely make it much simpler? 
> 
> The idea to handle RO->RW without mmu_lock is very neat, but the
> complexity with shadow is horrible.
> 


I have posted the v2 that is fairly simple, please review that one. :)
Thank you, Marcelo!