Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932294AbXADGMY (ORCPT ); Thu, 4 Jan 2007 01:12:24 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932295AbXADGMY (ORCPT ); Thu, 4 Jan 2007 01:12:24 -0500 Received: from smtp0.osdl.org ([65.172.181.24]:51013 "EHLO smtp.osdl.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932294AbXADGMX (ORCPT ); Thu, 4 Jan 2007 01:12:23 -0500 Date: Wed, 3 Jan 2007 22:12:20 -0800 From: Andrew Morton To: Nick Piggin Cc: Linus Torvalds , Andrea Gelmini , Linux Kernel Mailing List Subject: Re: VM: Fix nasty and subtle race in shared mmap'ed page writeback Message-Id: <20070103221220.c4589831.akpm@osdl.org> In-Reply-To: <459C98BF.5080409@yahoo.com.au> References: <200612291859.kBTIx2kq031961@hera.kernel.org> <20061229224309.GA23445@gelma.net> <459734CE.1090001@yahoo.com.au> <20061231135031.GC23445@gelma.net> <459C7B24.8080008@yahoo.com.au> <20070103214121.997be3e6.akpm@osdl.org> <459C98BF.5080409@yahoo.com.au> X-Mailer: Sylpheed version 2.2.7 (GTK+ 2.8.17; x86_64-unknown-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: 1201 Lines: 28 On Thu, 04 Jan 2007 17:03:43 +1100 Nick Piggin wrote: > > That bug was introduced in 2.6.19, with the dirty page tracking patches. > > > > 2.6.18 and earlier used ->private_lock coverage in try_to_free_buffers() to > > prevent it. > > Ohh, right you are, I was looking at 2.6.19 sources. The comments above > ttfb match that as well. Curious that the dirty page patches were allowed > to mess with this... Frankly, those patches scared the crap out of me, specifically because of the delicacy and complexity of the various dirtiness state coherencies. But I just didn't have the bandwidth to go through them with a sufficiently fine toothcomb, sorry. > Anyway that leaves us with the question of why Andrea's database is getting > corrupted. Hopefully he can give us a minimal test-case. It'd odd that stories of pre-2.6.19 BerkeleyDB corruption are now coming out of the woodwork. It's the first I've ever heard of them. - 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/