From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932244AbXCZTYY (ORCPT ); Mon, 26 Mar 2007 15:24:24 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932247AbXCZTYY (ORCPT ); Mon, 26 Mar 2007 15:24:24 -0400 Received: from smtp-outbound-1.vmware.com ([65.113.40.141]:37549 "EHLO smtp-outbound-1.vmware.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932244AbXCZTYX (ORCPT ); Mon, 26 Mar 2007 15:24:23 -0400 Message-ID: <46082BE6.30402@vmware.com> Date: Mon, 26 Mar 2007 12:24:06 -0800 From: Zachary Amsden User-Agent: Thunderbird 1.5.0.10 (X11/20070221) MIME-Version: 1.0 To: David Rientjes CC: Andrew Morton , Hugh Dickins , linux-kernel@vger.kernel.org Subject: Re: [patch -mm] i386: use pte_update_defer in ptep_test_and_clear_{dirty,young} References: In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org David Rientjes wrote: > Date: Sun, 25 Mar 2007 23:07:43 -0800 > From: Zachary Amsden > > If you actually clear the bit, you need to: > > + pte_update_defer(vma->vm_mm, addr, ptep); > > The reason is, when updating PTEs, the hypervisor must be notified. Using > atomic operations to do this is fine for all hypervisors I am aware of. > However, for hypervisors which shadow page tables, if these PTE > modifications are not trapped, you need a post-modification call to fulfill > the update of the shadow page table. > > Cc: Zachary Amsden > Cc: Hugh Dickins > Signed-off-by: David Rientjes > Acked-by: Zachary Amsden David, thanks for cleaning this up.