From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933807AbbFJSme (ORCPT ); Wed, 10 Jun 2015 14:42:34 -0400 Received: from arcturus.aphlor.org ([188.246.204.175]:51434 "EHLO arcturus.aphlor.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754270AbbFJSmZ (ORCPT ); Wed, 10 Jun 2015 14:42:25 -0400 Date: Wed, 10 Jun 2015 14:42:15 -0400 From: Dave Jones To: Chris Mason Cc: jbacik@fb.com, dsterba@suse.cz, Linux Kernel Subject: Re: [4.1-rc7] btrfs related VM_BUG_ON in filemap.c Message-ID: <20150610184215.GA32359@codemonkey.org.uk> Mail-Followup-To: Dave Jones , Chris Mason , jbacik@fb.com, dsterba@suse.cz, Linux Kernel References: <20150610134017.GA14803@codemonkey.org.uk> <55787743.4070308@fb.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <55787743.4070308@fb.com> User-Agent: Mutt/1.5.23 (2014-03-12) X-Spam-Score: -2.9 (--) X-Spam-Report: Spam report generated by SpamAssassin on "arcturus.aphlor.org" Content analysis details: (-2.9 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -1.0 ALL_TRUSTED Passed through trusted hosts only via SMTP -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] X-Authenticated-User: davej@codemonkey.org.uk Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jun 10, 2015 at 01:43:31PM -0400, Chris Mason wrote: > On 06/10/2015 09:40 AM, Dave Jones wrote: > > Found this on serial console this morning. The machine had rebooted itself shortly > > afterwards (surprising, given I don't have panic-on-oops or similar set). > > > > We had one other report of this a few months ago. Josef and I read > through all of this and decided it was impossible, so someone else must > be holding on to that page and unlocking it. > > (that someone else could easily be btrfs, just not in this code path) > > so...what horrible things have you been up to? Not sure exactly. I'll try and dig in some when I get home tonight. I do seem to be able to reproduce it fairly easily at least. (Twice this morning). Dave