From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ns211617.ip-188-165-215.eu ([188.165.215.42]:45442 "EHLO mx.speed47.net" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751768AbbJVKGT (ORCPT ); Thu, 22 Oct 2015 06:06:19 -0400 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Date: Thu, 22 Oct 2015 12:06:16 +0200 From: =?UTF-8?Q?St=C3=A9phane_Lesimple?= To: fdmanana@gmail.com Cc: Erkki Seppala , linux-btrfs@vger.kernel.org Subject: Re: BTRFS BUG at insert_inline_extent_backref+0xe3/0xf0 while rebalancing In-Reply-To: References: Message-ID: Sender: linux-btrfs-owner@vger.kernel.org List-ID: Le 2015-10-22 10:53, Filipe Manana a écrit : > On Thu, Oct 22, 2015 at 6:32 AM, Erkki Seppala > wrote: >> Hello, >> >> Recently I added daily rebalancing to my cron.d (after finding myself >> in >> the no-space-situation), and not long after that, I found my PC had >> crashed over night. Having no sign in the logs anywhere (not even over >> network even though there should be) I had nothing to go on, but this >> night it crashed again after starting the rebalance, and this time >> there >> was some information on the kernel log. >> >> Kernel version: 4.2.3 (package linux-image-4.2.0-1-amd64 version >> 4.2.3-1 >> from Debian Unstable) >> >> The dump is available at: >> >> http://www.modeemi.fi/~flux/btrfs/btrfs-BUG-2015-10-55.txt >> >> The log is available as well (stripped some unrelated USB- and >> firewall >> logging, showing that last evening there was some kernel task hung for >> 120 seconds; but it's in another btrfs filesystem and is another >> story): >> >> http://www.modeemi.fi/~flux/btrfs/btrfs-2015-10-55.txt >> >> I'm not quite sure which of the btrfs balance commands caused the >> issue. But there is my script: >> >> #!/bin/sh >> fs="$1" >> if [ -z "$fs" ]; then >> echo usage: btrfs-balance / 0 1 5 10 20 50 >> exit 1 >> fi >> fs="$1" >> shift >> for usage in d m; do for a in "$@"; do date; /bin/btrfs balance start >> "$fs" -v -${usage}usage=$a; done; done >> >> And it was started at 07:30 with: >> >> /usr/local/sbin/btrfs-balance / 0 1 2 5 10 20 30 50 70 >> >> I should add that the filesystem in question is backed by MD RAID10 >> and >> that is backed by four SSDs, so it's reasonably fast in IO, if that >> affects anything. There should have been no much competing IO at the >> time of the occurrence. >> >> Before Duncan asks ;-), I only have a moderate number of subvolumes >> and >> snapshots, ie. one subvolume for each of /, /var/log/journal and >> /home, >> 24 snapshots of / and /home plus <10 snapshots of /. >> >> Before that balance there was another balance on a another BTRFS >> RAID10, >> but given the time stamp I think I can easily say it wasn't the cause. >> >> I don't really have other 'solutions' than disabling the rebalancing >> for >> the time being, and only use it as-needed as I had earlier done.. > > Try this (just sent a few minutes ago): > https://patchwork.kernel.org/patch/7463161/ Awesome, I'll also try it right now under 4.3.0-rc6. My system is currently hit so hard by this bug that it no longer survives a balance for longer than a few minutes. Will keep you posted on the outcome. Thanks, -- Stéphane.