From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934918AbeEINze (ORCPT ); Wed, 9 May 2018 09:55:34 -0400 Received: from imap.thunk.org ([74.207.234.97]:59904 "EHLO imap.thunk.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934693AbeEINzc (ORCPT ); Wed, 9 May 2018 09:55:32 -0400 Date: Wed, 9 May 2018 09:55:28 -0400 From: "Theodore Y. Ts'o" To: Dave Chinner Cc: Dmitry Vyukov , syzbot , "Darrick J. Wong" , LKML , linux-xfs@vger.kernel.org, syzkaller-bugs Subject: Re: WARNING: bad unlock balance in xfs_iunlock Message-ID: <20180509135528.GE28388@thunk.org> Mail-Followup-To: "Theodore Y. Ts'o" , Dave Chinner , Dmitry Vyukov , syzbot , "Darrick J. Wong" , LKML , linux-xfs@vger.kernel.org, syzkaller-bugs References: <20180403043854.GL1150@dastard> <20180501225159.GY23861@dastard> <20180509005011.GP23861@dastard> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180509005011.GP23861@dastard> User-Agent: Mutt/1.9.5 (2018-04-13) X-SA-Exim-Connect-IP: X-SA-Exim-Mail-From: tytso@thunk.org X-SA-Exim-Scanned: No (on imap.thunk.org); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org >>> C reproducer: https://syzkaller.appspot.com/x/repro.c?id=5719304272084992 >>> syzkaller reproducer: >>> https://syzkaller.appspot.com/x/repro.syz?id=5767783983874048 >> >> What a mess. A hand built, hopelessly broken filesystem image made >> up of hex dumps, written into a mmap()d region of memory, then >> copied into a tmpfs file and mounted with the loop device. >> >> Engineers that can debug broken filesystems don't grow on trees. If >> we are to have any hope of understanding what the hell this test is >> doing, the bot needs to supply us with a copy of the built >> filesystem image the test uses. We need to be able to point forensic >> tools at the image to decode all the structures into human readable >> format - if we are forced to do that by hand or jump through hoops >> to create our own filesystem image than I'm certainly not going to >> waste time looking at these reports... > > Hi Dave, > > Here is the image: > https://drive.google.com/file/d/1jzhGGe5SBJcqfsjxCLHoh4Kazke1oTfC/view A suggestion --- insteading of forcing human beings --- either overworked file system developers, or understaffed fuzzing tool teams, to have to manually pull out the file system image out from the C repro, if it's too hard to add a link where the file system iamge can be downloaded from the Syzkaller web application --- how about adding an option to the C repro template which causes it to dump the image to a file and then immediately exit? - Ted