Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1763340AbXHVRvG (ORCPT ); Wed, 22 Aug 2007 13:51:06 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1764871AbXHVRut (ORCPT ); Wed, 22 Aug 2007 13:50:49 -0400 Received: from netops-testserver-3-out.sgi.com ([192.48.171.28]:38100 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1764148AbXHVRus (ORCPT ); Wed, 22 Aug 2007 13:50:48 -0400 Date: Wed, 22 Aug 2007 10:50:47 -0700 (PDT) From: Christoph Lameter X-X-Sender: clameter@schroedinger.engr.sgi.com To: Shaohua Li cc: lkml , kamezawa.hiroyu@jp.fujitsu.com Subject: Re: bug in migrate page In-Reply-To: <1187748489.8474.21.camel@sli10-conroe.sh.intel.com> Message-ID: References: <1187748489.8474.21.camel@sli10-conroe.sh.intel.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 861 Lines: 18 On Wed, 22 Aug 2007, Shaohua Li wrote: > commit dc386d4d1e98bb39fb967ee156cd456c802fc692 adds rcu_read_lock, but > some routines in the lock range might sleep (like lock_buffer, > aops->writepage), I saw a 'sleep in atomic' warning. It appears the > patch has several versions before. Doing rcu_read_lock in PageAnon > sounds break the case of PageAnon(page) && PageSwapCache(page), > as .writepage might be called. The dummy anon patch maybe is ok. Ok so we agree that .writepage is not used. Anonymous pages also do not not have buffers. Only taking the rcu lock on page_anon() would suffice to fix this right? - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/