From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Wed, 3 Oct 2001 12:14:41 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Wed, 3 Oct 2001 12:14:31 -0400 Received: from chunnel.redhat.com ([199.183.24.220]:51706 "EHLO sisko.scot.redhat.com") by vger.kernel.org with ESMTP id ; Wed, 3 Oct 2001 12:14:23 -0400 Date: Wed, 3 Oct 2001 17:14:51 +0100 From: "Stephen C. Tweedie" To: linux-kernel@vger.kernel.org Subject: Re: ReiserFS data corruption in very simple configuration Message-ID: <20011003171451.A5209@redhat.com> In-Reply-To: <200109221000.GAA11263@out-of-band.media.mit.edu> <15276.34915.301069.643178@beta.reiserfs.com> <20010925131304.I23320@mikef-linux.matchmail.com> <20010926154311.C12560@redhat.com> <20010930203831.A25387@mikef-linux.matchmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5i In-Reply-To: <20010930203831.A25387@mikef-linux.matchmail.com>; from mfedyk@matchmail.com on Sun, Sep 30, 2001 at 08:38:31PM -0700 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hi, On Sun, Sep 30, 2001 at 08:38:31PM -0700, Mike Fedyk wrote: > >From what you're describing, it looks like the contents of test after a > truncate won't be overwritten by another transaction until the deletion of > those blocks has made it to disk... So, while in ordered, or journal mode, > I'd end up with "a" in test, but with writeback mode there is no such > guarantee. > > Am I missing something? > > Are there any known cases where ext3 will not be able to recover pervious > data when a write wasn't able to complete? It depends on what the application is doing. Applications often open an existing file with O_TRUNC, write to it, then close it. If you crash between the truncate and the write being committed, then you'll get a perfectly legal, sane, consistent, empty file on recovery. --Stephen