From: Eric Sandeen Subject: Re: Mild filesystem corruption on ext4 (no journal) Date: Fri, 05 Jun 2009 10:20:44 -0500 Message-ID: <4A2937CC.7070503@redhat.com> References: <4A28F83F.4030704@tuffmail.co.uk> <4A292E61.3050204@gmail.com> <4A293084.5010400@tuffmail.co.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: Aioanei Rares , linux-ext4@vger.kernel.org, Linux Kernel Mailing List To: Alan Jenkins Return-path: Received: from mx2.redhat.com ([66.187.237.31]:38887 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751088AbZFEPUq (ORCPT ); Fri, 5 Jun 2009 11:20:46 -0400 In-Reply-To: <4A293084.5010400@tuffmail.co.uk> Sender: linux-ext4-owner@vger.kernel.org List-ID: Alan Jenkins wrote: > Aioanei Rares wrote: >> I suspect, although I might be wrong, that this is not a kernel-related >> problem. > > "To try and rule out a faulty userspace program, I marked the file as > read-only (chmod a-w) and immutable (chattr +i). After a reboot, the > file was still read-only and immutable, yet it still became corrupted." > > Since the immutable bit is not respected, I tend to think it is a kernel > problem. Unless the filesystem isn't getting unmounted/flushed properly > for some reason... but I thought the modern kernel had that covered. > > I agree it is very suspicious this happens only after upgrading libc. > I'll see if I can find an individual change in libc locale-handling that > might trigger this. Maybe you could try some things in your shutdown script, such as explicitly fsyncing the file, or bmapping it with filefrag, or dropping caches and rereading it... see what the state is just before the shutdown compared to after the reboot. -Eric