From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 15198C4320E for ; Wed, 25 Aug 2021 21:45:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F037E61106 for ; Wed, 25 Aug 2021 21:45:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234367AbhHYVqd (ORCPT ); Wed, 25 Aug 2021 17:46:33 -0400 Received: from mail109.syd.optusnet.com.au ([211.29.132.80]:56862 "EHLO mail109.syd.optusnet.com.au" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231559AbhHYVqc (ORCPT ); Wed, 25 Aug 2021 17:46:32 -0400 Received: from dread.disaster.area (pa49-195-182-146.pa.nsw.optusnet.com.au [49.195.182.146]) by mail109.syd.optusnet.com.au (Postfix) with ESMTPS id 40F32845F7; Thu, 26 Aug 2021 07:45:38 +1000 (AEST) Received: from dave by dread.disaster.area with local (Exim 4.92.3) (envelope-from ) id 1mJ0iE-004w5c-8M; Thu, 26 Aug 2021 07:45:34 +1000 Date: Thu, 26 Aug 2021 07:45:34 +1000 From: Dave Chinner To: syzbot Cc: a@unstable.cc, axboe@kernel.dk, b.a.t.m.a.n@lists.open-mesh.org, davem@davemloft.net, djwong@kernel.org, josef@toxicpanda.com, linux-kernel@vger.kernel.org, linux-xfs@vger.kernel.org, mareklindner@neomailbox.ch, mchristi@redhat.com, netdev@vger.kernel.org, sw@simonwunderlich.de, syzkaller-bugs@googlegroups.com Subject: Re: [syzbot] INFO: task hung in __xfs_buf_submit (2) Message-ID: <20210825214534.GM3657114@dread.disaster.area> References: <0000000000002fc21105ca657edf@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <0000000000002fc21105ca657edf@google.com> X-Optus-CM-Score: 0 X-Optus-CM-Analysis: v=2.3 cv=Tu+Yewfh c=1 sm=1 tr=0 a=QpfB3wCSrn/dqEBSktpwZQ==:117 a=QpfB3wCSrn/dqEBSktpwZQ==:17 a=kj9zAlcOel0A:10 a=MhDmnRu9jo8A:10 a=VwQbUJbxAAAA:8 a=edf1wS77AAAA:8 a=20KFwNOVAAAA:8 a=hSkVLCK3AAAA:8 a=7-415B0cAAAA:8 a=uqB4RbaozhEYDSnVuTIA:9 a=CjuIK1q_8ugA:10 a=AjGcO6oz07-iQ99wixmX:22 a=DcSpbTIhAlouE1Uv7lRv:22 a=cQPPKAXgyycSBL8etih5:22 a=biEYGPWJfzWAr4FL6Ov7:22 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Aug 25, 2021 at 10:22:21AM -0700, syzbot wrote: > Hello, > > syzbot found the following issue on: > > HEAD commit: 6e764bcd1cf7 Merge tag 'for-linus' of git://git.kernel.org.. > git tree: upstream > console output: https://syzkaller.appspot.com/x/log.txt?x=10504885300000 > kernel config: https://syzkaller.appspot.com/x/.config?x=2fd902af77ff1e56 > dashboard link: https://syzkaller.appspot.com/bug?extid=4bb1622c9a583bb6f9f2 > compiler: Debian clang version 11.0.1-2, GNU ld (GNU Binutils for Debian) 2.35.1 > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=14427606300000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=149b3cce300000 > > The issue was bisected to: > > commit 887e975c4172d0d5670c39ead2f18ba1e4ec8133 > Author: Mike Christie > Date: Tue Aug 13 16:39:51 2019 +0000 > > nbd: add missing config put > > bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=11980ad5300000 > final oops: https://syzkaller.appspot.com/x/report.txt?x=13980ad5300000 > console output: https://syzkaller.appspot.com/x/log.txt?x=15980ad5300000 > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > Reported-by: syzbot+4bb1622c9a583bb6f9f2@syzkaller.appspotmail.com > Fixes: 887e975c4172 ("nbd: add missing config put") XFS is waiting on IO completion to be signalled from the block device, and the bisect points to commit fixing a problem with a block device processing IO timeout errors. IOWs, the above commit is probably exposing a latent bug in the commit that changes all the error handling in nbd to fix completion races in IO completion. The commit message for 8f3ea35929a0 ("nbd: handle unexpected replies better") also makes mention of races with timeout errors, and the above commit is touching the timeout error handling. Josef, this one looks like it is yours... Cheers, Dave. -- Dave Chinner david@fromorbit.com From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Thu, 26 Aug 2021 07:45:34 +1000 From: Dave Chinner Subject: Re: [syzbot] INFO: task hung in __xfs_buf_submit (2) Message-ID: <20210825214534.GM3657114@dread.disaster.area> References: <0000000000002fc21105ca657edf@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <0000000000002fc21105ca657edf@google.com> Reply-To: The list for a Better Approach To Mobile Ad-hoc Networking List-Id: The list for a Better Approach To Mobile Ad-hoc Networking List-Archive: List-Help: List-Post: List-Subscribe: List-Unsubscribe: To: syzbot Cc: a@unstable.cc, axboe@kernel.dk, b.a.t.m.a.n@lists.open-mesh.org, davem@davemloft.net, djwong@kernel.org, josef@toxicpanda.com, linux-kernel@vger.kernel.org, linux-xfs@vger.kernel.org, mareklindner@neomailbox.ch, mchristi@redhat.com, netdev@vger.kernel.org, syzkaller-bugs@googlegroups.com On Wed, Aug 25, 2021 at 10:22:21AM -0700, syzbot wrote: > Hello, > > syzbot found the following issue on: > > HEAD commit: 6e764bcd1cf7 Merge tag 'for-linus' of git://git.kernel.org.. > git tree: upstream > console output: https://syzkaller.appspot.com/x/log.txt?x=10504885300000 > kernel config: https://syzkaller.appspot.com/x/.config?x=2fd902af77ff1e56 > dashboard link: https://syzkaller.appspot.com/bug?extid=4bb1622c9a583bb6f9f2 > compiler: Debian clang version 11.0.1-2, GNU ld (GNU Binutils for Debian) 2.35.1 > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=14427606300000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=149b3cce300000 > > The issue was bisected to: > > commit 887e975c4172d0d5670c39ead2f18ba1e4ec8133 > Author: Mike Christie > Date: Tue Aug 13 16:39:51 2019 +0000 > > nbd: add missing config put > > bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=11980ad5300000 > final oops: https://syzkaller.appspot.com/x/report.txt?x=13980ad5300000 > console output: https://syzkaller.appspot.com/x/log.txt?x=15980ad5300000 > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > Reported-by: syzbot+4bb1622c9a583bb6f9f2@syzkaller.appspotmail.com > Fixes: 887e975c4172 ("nbd: add missing config put") XFS is waiting on IO completion to be signalled from the block device, and the bisect points to commit fixing a problem with a block device processing IO timeout errors. IOWs, the above commit is probably exposing a latent bug in the commit that changes all the error handling in nbd to fix completion races in IO completion. The commit message for 8f3ea35929a0 ("nbd: handle unexpected replies better") also makes mention of races with timeout errors, and the above commit is touching the timeout error handling. Josef, this one looks like it is yours... Cheers, Dave. -- Dave Chinner david@fromorbit.com