From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752103AbeBHOtf (ORCPT ); Thu, 8 Feb 2018 09:49:35 -0500 Received: from mga06.intel.com ([134.134.136.31]:65430 "EHLO mga06.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750961AbeBHOtd (ORCPT ); Thu, 8 Feb 2018 09:49:33 -0500 X-Amp-Result: UNSCANNABLE X-Amp-File-Uploaded: False X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.46,479,1511856000"; d="scan'208";a="16300267" Date: Thu, 8 Feb 2018 06:49:18 -0800 From: Andi Kleen To: Jan Kara Cc: syzbot , akpm@linux-foundation.org, aryabinin@virtuozzo.com, jlayton@redhat.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, mgorman@techsingularity.net, mingo@kernel.org, rgoldwyn@suse.com, syzkaller-bugs@googlegroups.com, linux-fsdevel@vger.kernel.org Subject: Re: INFO: task hung in sync_blockdev Message-ID: <20180208144918.GF10945@tassilo.jf.intel.com> References: <001a11447070ac6fcb0564a08cb1@google.com> <20180207155229.GC10945@tassilo.jf.intel.com> <20180208092839.ebe5rk6mtvkk5da4@quack2.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180208092839.ebe5rk6mtvkk5da4@quack2.suse.cz> User-Agent: Mutt/1.9.1 (2017-09-22) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > > It seems multiple processes deadlocked on the bd_mutex. > > Unfortunately there's no backtrace for the lock acquisitions, > > so it's hard to see the exact sequence. > > Well, all in the report points to a situation where some IO was submitted > to the block device and never completed (more exactly it took longer than > those 120s to complete that IO). It would need more digging into the Are you sure? I didn't think outstanding IO would take bd_mutex. -Andi