From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephane Chazelas Subject: BUG() in btrfs-fixup (Was: btrfs invalid opcode) Date: Wed, 27 Jul 2011 09:33:24 +0100 Message-ID: References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: linux-btrfs@vger.kernel.org To: Jeremy Sanders Return-path: In-Reply-To: List-ID: 2011-07-25 17:38:10 +0100, Jeremy Sanders: > I'm afraid this is a rather old kernel, 2.6.35.13-92.fc14.x86_64, but this > error looks rather similiar to > http://www.spinics.net/lists/linux-btrfs/msg11053.html > > Has this been fixed? I was simultaneously doing rsyncs into different > subvolumes (one reading and one writing). [...] > [454244.123523] kernel BUG at fs/btrfs/inode.c:1528! [...] > [454244.124338] Pid: 3158, comm: btrfs-fixup-0 Not tainted > 2.6.35.13-92.fc14.x86_64 #1 C51MCP51/C51GM03 > [454244.124338] RIP: 0010:[] [] > btrfs_writepage_fixup_worker+0xde/0x118 [btrfs] [...] Hi Jeremy, glad I'm not the only one with that issue. That may renew the interest in it... I don't think much progress has been made on it. We could compare our experience to see what contributes to its occurrence. It occurs (quite reproducibly) for me when rsyncing from a multi-device multi-subvolume btrfs fs (mounted with compress-force) onto a single device, no subvolume btrfs fs also mounted with compress-force. It also happens when the target is mounted with compress instead of compress-force but not if I leave out "compress". I only get one occurrence of those BUG()s until I reboot. After the occurrence of that BUG(), I saw a number of misbehaviors that may or may not be linked to it: - btrfs eating all memory (mostly in the btrfs_inode_cache slab) resulting in crash. That doesn't happen anymore since I'm mounting with no atime and use CONFIG_SLUB (though I suspect it's noatime alone that did the trick) - occasionally, 20 to 95% of write(2) system calls to files on the source FS take 4 seconds, making it hardly usable. I also notice a flush-btrfs-1 stuck in "D" state How does that compare with your experience? -- Stephane