Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761094AbYCWLHo (ORCPT ); Sun, 23 Mar 2008 07:07:44 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1759678AbYCWLHX (ORCPT ); Sun, 23 Mar 2008 07:07:23 -0400 Received: from bombadil.infradead.org ([18.85.46.34]:50172 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759393AbYCWLHV (ORCPT ); Sun, 23 Mar 2008 07:07:21 -0400 Subject: Re: ext3 lockdep warning in 2.6.25-rc6 From: Peter Zijlstra To: Erez Zadok Cc: sct@redhat.com, akpm@linux-foundation.org, adilger@clusterfs.com, linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org In-Reply-To: <200803222234.m2MMYRJo005108@agora.fsl.cs.sunysb.edu> References: <200803222234.m2MMYRJo005108@agora.fsl.cs.sunysb.edu> Content-Type: text/plain Date: Sun, 23 Mar 2008 12:06:27 +0100 Message-Id: <1206270388.6437.90.camel@lappy> Mime-Version: 1.0 X-Mailer: Evolution 2.22.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1385 Lines: 29 On Sat, 2008-03-22 at 18:34 -0400, Erez Zadok wrote: > In message <1206207527.6437.83.camel@lappy>, Peter Zijlstra writes: > > On Sat, 2008-03-22 at 10:37 -0400, Erez Zadok wrote: > > > I was building a kernel using "make -j 4" inside a unionfs, mounted on top > > > of ext3. The kernel is vanilla 2.6.25-rc6 plus unionfs patches. At some > > > point I forced a cache flush using "echo 3 > /proc/sys/vm/drop_caches" and I > > > got the lockdep warning below. Note that unionfs doesn't appear to be > > > involved in this lockdep warning at all, so I suspect this is probably an > > > issue between jbd and ext3 directly. > > > > Known issue, drop_caches isn't production quality. > > Is this a general problem with drop_caches, or its interaction with > ext3/jbd? If I get a similar lockdep warning with other file systems, > should I bother to report this to the respective f/s maintainers? Its a generic problem with drop_caches. If you look in the lkml archives you'll find similar reports against XFS and others. Some time ago Andrew outlined a fix for it, but so far that hasn't happened: http://lkml.org/lkml/2007/2/23/46 -- 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/