From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S271710AbTGYFNU (ORCPT ); Fri, 25 Jul 2003 01:13:20 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S271924AbTGYFNU (ORCPT ); Fri, 25 Jul 2003 01:13:20 -0400 Received: from ppp-217-133-42-200.cust-adsl.tiscali.it ([217.133.42.200]:53633 "EHLO x30.random") by vger.kernel.org with ESMTP id S271710AbTGYFNT (ORCPT ); Fri, 25 Jul 2003 01:13:19 -0400 Date: Fri, 25 Jul 2003 01:28:18 -0400 From: Andrea Arcangeli To: "Sergey S. Kostyliov" Cc: linux-kernel@vger.kernel.org Subject: Re: 2.4.22pre6aa1 Message-ID: <20030725052818.GA6440@x30.random> References: <200307231521.15897.rathamahata@php4.ru> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200307231521.15897.rathamahata@php4.ru> User-Agent: Mutt/1.4i X-GPG-Key: 1024D/68B9CB43 13D9 8355 295F 4823 7C49 C012 DFA1 686E 68B9 CB43 X-PGP-Key: 1024R/CB4660B9 CC A0 71 81 F4 A0 63 AC C0 4B 81 1D 8C 15 C8 E5 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jul 23, 2003 at 03:21:15PM +0400, Sergey S. Kostyliov wrote: > Hello Andrea, > > This is during `swapoff -a`, on a heavily loaded box: > > ksymoops 2.4.9 on i686 2.4.22-pre6aa1. Options used > -V (default) > -k /proc/ksyms (default) > -l /proc/modules (default) > -o /lib/modules/2.4.22-pre6aa1/ (default) > -m /usr/src/linux/System.map (default) > > Warning: You did not tell me where to find symbol information. I will > assume that the log matches the kernel and modules that are running > right now and I'll use the default options above for symbol resolution. > If the current kernel and/or modules do not match the log, you can get > more accurate output by telling me the kernel version and where to find > map, modules, ksyms etc. ksymoops -h explains the options. > > Error (regular_file): read_system_map stat /usr/src/linux/System.map failed > ksymoops: No such file or directory > kernel BUG at shmem.c:490! hmm, 2.4.22pre6aa1 was the first 2.4 largepages port to the >=22pre shmfs backport from 2.5. It could be a bug in 2.5, or a bug present only in the backport of the 2.5 code to 22pre, or even a bug only present in -aa due the largepage patch ported on top of the backport included in 22pre. I'll have a closer look at it tomorrow. The place where it crashed is: BUG_ON(inode->i_blocks); it might be only a minor accounting issue. It needs some auditing. I'm afraid you're the first one testing the shmfs backport in 22pre + the largepage support patch in my tree with a big app doing swapoff at the same time. Are you using bigpages btw? thank you very much for the feedback, Andrea PS. shall this give us relevant problems in the debugging/auditing, I'll just give you a patch to backout the backport and go back to the shmfs code in 2.4.21rc8aa1 that is running rock solid in production with largepages (I doubt you need the loop device on top of shmfs anyways). I prefer not to spend much time on new 2.4 features.