From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sasha Levin Subject: Re: [PATCH v4 00/32] ldisc patchset Date: Thu, 21 Feb 2013 08:16:32 -0500 Message-ID: <51261E30.9040907@gmail.com> References: <1360095638-6624-1-git-send-email-peter@hurleysoftware.com> <1361390599-15195-1-git-send-email-peter@hurleysoftware.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from mail-vb0-f49.google.com ([209.85.212.49]:46038 "EHLO mail-vb0-f49.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752448Ab3BUNQt (ORCPT ); Thu, 21 Feb 2013 08:16:49 -0500 In-Reply-To: <1361390599-15195-1-git-send-email-peter@hurleysoftware.com> Sender: linux-serial-owner@vger.kernel.org List-Id: linux-serial@vger.kernel.org To: Peter Hurley Cc: Greg Kroah-Hartman , Jiri Slaby , Sebastian Andrzej Siewior , linux-kernel@vger.kernel.org, linux-serial@vger.kernel.org, Ilya Zykov , Dave Jones , Michael Ellerman , Shawn Guo On 02/20/2013 03:02 PM, Peter Hurley wrote: > Sasha and Dave, my trinity testbeds die in other areas right now; > I would really appreciate if you would please re-test this series. Hi Peter, I saw this twice in overnight fuzzing: [ 1473.912280] ================================= [ 1473.913180] [ BUG: bad contention detected! ] [ 1473.914071] 3.8.0-next-20130220-sasha-00038-g1ad55df-dirty #8 Tainted: G W [ 1473.915684] --------------------------------- [ 1473.916549] kworker/1:1/361 is trying to contend lock (&tty->ldisc_sem) at: [ 1473.918031] [] tty_ldisc_ref+0x1f/0x60 [ 1473.919060] but there are no locks held! [ 1473.919813] [ 1473.919813] other info that might help us debug this: [ 1473.920044] 2 locks held by kworker/1:1/361: [ 1473.920044] #0: (events){.+.+.+}, at: [] process_one_work+0x228/0x6a0 [ 1473.920044] #1: ((&buf->work)){+.+...}, at: [] process_one_work+0x228/0x6a0 [ 1473.920044] [ 1473.920044] stack backtrace: [ 1473.920044] Pid: 361, comm: kworker/1:1 Tainted: G W 3.8.0-next-20130220-sasha-00038-g1ad55df-dirty #8 [ 1473.920044] Call Trace: [ 1473.920044] [] ? tty_ldisc_ref+0x1f/0x60 [ 1473.920044] [] print_lock_contention_bug+0xf6/0x110 [ 1473.920044] [] lock_contended+0x213/0x4e0 [ 1473.920044] [] ldsem_down_read_trylock+0xb1/0xc0 [ 1473.920044] [] tty_ldisc_ref+0x1f/0x60 [ 1473.920044] [] flush_to_ldisc+0x37/0x1a0 [ 1473.920044] [] process_one_work+0x366/0x6a0 [ 1473.920044] [] ? process_one_work+0x228/0x6a0 [ 1473.920044] [] worker_thread+0x238/0x370 [ 1473.920044] [] ? rescuer_thread+0x310/0x310 [ 1473.920044] [] kthread+0xe3/0xf0 [ 1473.920044] [] ? flush_kthread_work+0x1f0/0x1f0 [ 1473.920044] [] ret_from_fork+0x7c/0xb0 [ 1473.920044] [] ? flush_kthread_work+0x1f0/0x1f0 Thanks, Sasha