From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751699Ab0EANDi (ORCPT ); Sat, 1 May 2010 09:03:38 -0400 Received: from mx1.redhat.com ([209.132.183.28]:14624 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750772Ab0EANDh (ORCPT ); Sat, 1 May 2010 09:03:37 -0400 Message-ID: <4BDC2664.40504@redhat.com> Date: Sat, 01 May 2010 09:02:28 -0400 From: Rik van Riel User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.7) Gecko/20100120 Fedora/3.0.1-1.fc12 Lightning/1.0b2pre Thunderbird/3.0.1 MIME-Version: 1.0 To: Andrea Arcangeli CC: Mel Gorman , Andrew Morton , Linux-MM , LKML , Minchan Kim , KAMEZAWA Hiroyuki , Christoph Lameter Subject: Re: [PATCH 2/2] mm,migration: Avoid race between shift_arg_pages() and rmap_walk() during migration by not migrating temporary stacks References: <1272529930-29505-1-git-send-email-mel@csn.ul.ie> <1272529930-29505-3-git-send-email-mel@csn.ul.ie> <20100429162120.GC22108@random.random> <20100430192235.GL22108@random.random> <20100501093926.GA19891@random.random> In-Reply-To: <20100501093926.GA19891@random.random> 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 05/01/2010 05:39 AM, Andrea Arcangeli wrote: > === > Subject: fix race between shift_arg_pages and rmap_walk > > From: Andrea Arcangeli > > migrate.c requires rmap to be able to find all ptes mapping a page at > all times, otherwise the migration entry can be instantiated, but it > can't be removed if the second rmap_walk fails to find the page. > > And split_huge_page() will have the same requirements as migrate.c > already has. > > Signed-off-by: Andrea Arcangeli Reviewed-by: Rik van Riel -- All rights reversed