From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx1.fusionio.com ([66.114.96.30]:33982 "EHLO mx1.fusionio.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751440Ab2GFOke (ORCPT ); Fri, 6 Jul 2012 10:40:34 -0400 Date: Fri, 6 Jul 2012 10:40:31 -0400 From: Chris Mason To: Sami Liedes CC: Jan Schmidt , "linux-btrfs@vger.kernel.org" Subject: Re: btrfs GPF in read_extent_buffer() while scrubbing with kernel 3.4.2 Message-ID: <20120706144030.GL7159@shiny> References: <20120703224756.GA21647@sli.dy.fi> <20120704001713.GA8986@sli.dy.fi> <4FF42876.8010309@jan-o-sch.net> <20120704160340.GA9770@sli.dy.fi> <4FF47168.9010405@jan-o-sch.net> <20120704202452.GA8996@sli.dy.fi> <4FF5998D.8020205@jan-o-sch.net> <20120705234739.GA9736@sli.dy.fi> <4FF6C12A.10305@jan-o-sch.net> <20120706143350.GA10427@sli.dy.fi> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" In-Reply-To: <20120706143350.GA10427@sli.dy.fi> Sender: linux-btrfs-owner@vger.kernel.org List-ID: On Fri, Jul 06, 2012 at 08:33:51AM -0600, Sami Liedes wrote: > On Fri, Jul 06, 2012 at 12:42:50PM +0200, Jan Schmidt wrote: > > I've no good idea at the moment how to go on. It might help to get a feeling if > > it's shifting around at least a little bit or really constant in the timing of > > occurrence. So can you please apply the next patch on top of the other two and > > give it some more failure tries? The "checksum mismatch [1234]" line will be of > > most interest. I'm also curious what the additional debug variables will say in > > the extended version of the very first printk. You can leave out the stack > > traces if you like, they won't matter much anyway. > > Ok. Also turned on CONFIG_DEBUG_PAGEALLOC and CONFIG_SLUB_DEBUG_ON as > suggested by Chris Mason. > > With those and the latest patch, there's an oops already at boot. I > don't have netconsole yet at that point, but here's the important > parts (sure I can capture it fully if you need). > > By the way, something seems to be untabifying your patches. I don't > know if it's on my side or yours, but at least some other patches I > receive via linux-btrfs contain tabs. Doing a M-x tabify in emacs > mostly makes them apply cleanly for me. > > Sami > > > ------------------------------------------------------------ > btrfs: disk space caching is enabled > BUG: unable to handle kernel NULL pointer dereference at 0000000000000150 > IP: [] check_node+0x138/0x250 [btrfs] This isn't from any of the new debugging. Can you please try it on an unpatched kernel? -chris