Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932613AbWLSBVv (ORCPT ); Mon, 18 Dec 2006 20:21:51 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932607AbWLSBVv (ORCPT ); Mon, 18 Dec 2006 20:21:51 -0500 Received: from smtp.osdl.org ([65.172.181.25]:39041 "EHLO smtp.osdl.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932613AbWLSBVu (ORCPT ); Mon, 18 Dec 2006 20:21:50 -0500 Date: Mon, 18 Dec 2006 17:21:26 -0800 From: Andrew Morton To: Linus Torvalds Cc: Andrei Popa , Peter Zijlstra , Linux Kernel Mailing List , Hugh Dickins , Florian Weimer , Marc Haber , Martin Michlmayr Subject: Re: 2.6.19 file content corruption on ext3 Message-Id: <20061218172126.0822b5d2.akpm@osdl.org> In-Reply-To: References: <1166314399.7018.6.camel@localhost> <20061217040620.91dac272.akpm@osdl.org> <1166362772.8593.2.camel@localhost> <20061217154026.219b294f.akpm@osdl.org> <1166460945.10372.84.camel@twins> <1166466272.10372.96.camel@twins> <1166468651.6983.6.camel@localhost> <1166471069.6940.4.camel@localhost> <1166476297.6862.1.camel@localhost> <1166485691.6977.6.camel@localhost> <1166488199.6950.2.camel@localhost> X-Mailer: Sylpheed version 2.2.7 (GTK+ 2.8.6; i686-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 X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1726 Lines: 40 On Mon, 18 Dec 2006 16:57:30 -0800 (PST) Linus Torvalds wrote: > What happens if you only ifdef out that single thing? > > The actual page-cleaning functions make sure to only clear the TAG_DIRTY > bit _after_ the page has been marked for writeback. Is there some ordering > constraint there, perhaps? > > I'm really reaching here. I'm trying to see the pattern, and I'm not > seeing it. I'm asking you to test things just to get more of a feel for > what triggers the failure, than because I actually have any kind of idea > of what the heck is going on. > > Andrew, Nick, Hugh - any ideas? If all of test_clear_page_dirty() has been commented out then the page will never become clean hence will never fall out of pagecache, so unless Andrei is doing a reboot before checking for corruption, perhaps the underlying data on-disk is incorrect, but we can't see it. Andrei, how _are_ you running this test? What's the exact sequence of steps? In particular, are you doing anything which would cause the corrupted file to be evicted from memory, thus forcing a read from disk? Such as unmounting and then remounting the filesystem? The point of my question is to check that the data is really incorrect on-disk, or whether it is incorrect in pagecache. Also, it'd be useful if you could determine whether the bug appears with the ext2 filesystem: do s/ext3/ext2/ in /etc/fstab, or boot with rootfstype=ext2 if it's the root filesystem. Thanks. - 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/