From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933340Ab2KEV4m (ORCPT ); Mon, 5 Nov 2012 16:56:42 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:55468 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933223Ab2KEV4a (ORCPT ); Mon, 5 Nov 2012 16:56:30 -0500 Date: Mon, 5 Nov 2012 13:56:28 -0800 From: Andrew Morton To: Naoya Horiguchi Cc: Tony Luck , Andi Kleen , Wu Fengguang , Ingo Molnar , "Jun'ichi Nomura" , linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH 1/2 v2] HWPOISON: fix action_result() to print out dirty/clean Message-Id: <20121105135628.db79602c.akpm@linux-foundation.org> In-Reply-To: <1351873993-9373-2-git-send-email-n-horiguchi@ah.jp.nec.com> References: <1351873993-9373-1-git-send-email-n-horiguchi@ah.jp.nec.com> <1351873993-9373-2-git-send-email-n-horiguchi@ah.jp.nec.com> X-Mailer: Sylpheed 3.0.2 (GTK+ 2.20.1; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 2 Nov 2012 12:33:12 -0400 Naoya Horiguchi wrote: > action_result() fails to print out "dirty" even if an error occurred on a > dirty pagecache, because when we check PageDirty in action_result() it was > cleared after page isolation even if it's dirty before error handling. This > can break some applications that monitor this message, so should be fixed. > > There are several callers of action_result() except page_action(), but > either of them are not for LRU pages but for free pages or kernel pages, > so we don't have to consider dirty or not for them. > > Note that PG_dirty can be set outside page locks as described in commit > 554940dc8c1e, so this patch does not completely closes the race window, > but just narrows it. I can find no commit 554940dc8c1e. What commit are you referring to here? This is one of the reasons why we ask people to refer to commits by both hash and by name, using the form 078de5f706ece3 ("userns: Store uid and gid values in struct cred with kuid_t and kgid_t types")