From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756230Ab1INJzY (ORCPT ); Wed, 14 Sep 2011 05:55:24 -0400 Received: from mx1.redhat.com ([209.132.183.28]:21830 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756057Ab1INJzX (ORCPT ); Wed, 14 Sep 2011 05:55:23 -0400 Message-ID: <4E7079FD.6050506@redhat.com> Date: Wed, 14 Sep 2011 12:55:09 +0300 From: Avi Kivity User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:6.0) Gecko/20110816 Thunderbird/6.0 MIME-Version: 1.0 To: Xiao Guangrong CC: Marcelo Tosatti , LKML , KVM Subject: Re: [PATCH v3 05/11] KVM: MMU: do not mark accessed bit on pte write path References: <4E5C4C20.3000403@cn.fujitsu.com> <4E5C4C8D.5040509@cn.fujitsu.com> <4E6F363E.9080000@redhat.com> <4E6FA117.1050707@cn.fujitsu.com> In-Reply-To: <4E6FA117.1050707@cn.fujitsu.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 09/13/2011 09:29 PM, Xiao Guangrong wrote: > On 09/13/2011 06:53 PM, Avi Kivity wrote: > > On 08/30/2011 05:35 AM, Xiao Guangrong wrote: > >> In current code, the accessed bit is always set when page fault occurred, > >> do not need to set it on pte write path > > > > What about speculative sptes that are then only accessed via emulation? > > > > The gfn is read and written only via emulation? I think this case is very > very rare? Probably... Marcelo? Can you think of another case where spte.accessed is needed? -- error compiling committee.c: too many arguments to function