From mboxrd@z Thu Jan  1 00:00:00 1970
From: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Subject: Re: [PATCH 08/13] KVM: MMU: fask check whether page is writable
Date: Fri, 13 Apr 2012 18:26:52 +0800
Message-ID: <4F87FF6C.1080403@linux.vnet.ibm.com>
References: <4F742951.7080003@linux.vnet.ibm.com> <4F742A74.1050304@linux.vnet.ibm.com> <4F7879A1.2020301@redhat.com> <4F7DDC6C.90304@gmail.com> <20120412230828.GA20207@amt.cnet>
Mime-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 7bit
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>
Return-path: <linux-kernel-owner@vger.kernel.org>
In-Reply-To: <20120412230828.GA20207@amt.cnet>
Sender: linux-kernel-owner@vger.kernel.org
List-Id: kvm.vger.kernel.org

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!