From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757561Ab1EXWUx (ORCPT ); Tue, 24 May 2011 18:20:53 -0400 Received: from lennier.cc.vt.edu ([198.82.162.213]:52654 "EHLO lennier.cc.vt.edu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757506Ab1EXWUw (ORCPT ); Tue, 24 May 2011 18:20:52 -0400 X-Mailer: exmh version 2.7.2 01/07/2005 with nmh-1.3-dev To: Andrew Morton , Ingo Molnar , Peter Zijlstra Cc: linux-kernel@vger.kernel.org Subject: 2.6.39-rc7-mmotm0512 lockdep splat in scheduler code From: Valdis.Kletnieks@vt.edu Mime-Version: 1.0 Content-Type: multipart/signed; boundary="==_Exmh_1306275571_2633P"; micalg=pgp-sha1; protocol="application/pgp-signature" Content-Transfer-Encoding: 7bit Date: Tue, 24 May 2011 18:19:31 -0400 Message-ID: <28171.1306275571@localhost> X-Mirapoint-Received-SPF: 198.82.161.152 auth3.smtp.vt.edu Valdis.Kletnieks@vt.edu 2 pass X-Mirapoint-IP-Reputation: reputation=neutral-1, source=Fixed, refid=n/a, actions=MAILHURDLE SPF TAG X-Junkmail-Status: score=10/50, host=zidane.cc.vt.edu X-Junkmail-Signature-Raw: score=unknown, refid=str=0001.0A02020A.4DDC2EF5.0055,ss=1,fgs=0, ip=0.0.0.0, so=2010-07-22 22:03:31, dmn=2009-09-10 00:05:08, mode=single engine X-Junkmail-IWF: false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --==_Exmh_1306275571_2633P Content-Type: text/plain; charset=us-ascii Sorry if this was reported already but I missed it on the lkml firehose.. Seen this morning at boot while configuring the sound card. Semi-reproducible, as it's tripped 3 times in the last 5 boots of this kernel. However, it hadn't tripped once in the previous 15 boots of that same kernel (odd, as it's same kernel binary and same initrd, and we're still on the initrd at this point). Not sure what changed to make it start happening. (/proc/interrupts lists: 48: 67445 66819 PCI-MSI-edge hda_intel) [ 2.511386] HDA Intel 0000:00:1b.0: setting latency timer to 64 [ 2.523230] [ 2.523231] =================================================== [ 2.523234] [ INFO: suspicious rcu_dereference_check() usage. ] [ 2.523236] --------------------------------------------------- [ 2.523238] kernel/sched_rt.c:1244 invoked rcu_dereference_check() without protection! [ 2.523241] [ 2.523241] other info that might help us debug this: [ 2.523242] [ 2.523244] [ 2.523245] rcu_scheduler_active = 1, debug_locks = 1 [ 2.523247] 1 lock held by irq/48-hda_inte/85: [ 2.523249] #0: (&rq->lock){-.-.-.}, at: [] post_schedule.part.20+0xf/0x45 [ 2.523259] [ 2.523260] stack backtrace: [ 2.523263] Pid: 85, comm: irq/48-hda_inte Not tainted 2.6.39-rc7-mmotm0512 #2 [ 2.523265] Call Trace: [ 2.523271] [] lockdep_rcu_dereference+0x9a/0xa2 [ 2.523275] [] find_lowest_rq+0xf9/0x174 [ 2.523279] [] find_lock_lowest_rq+0x2c/0xfe [ 2.523284] [] push_rt_task.part.60+0xac/0x156 [ 2.523288] [] post_schedule_rt+0x1a/0x23 [ 2.523291] [] post_schedule.part.20+0x2b/0x45 [ 2.523296] [] schedule+0x6f2/0x738 [ 2.523301] [] ? irq_thread_fn+0x29/0x29 [ 2.523305] [] irq_thread+0x173/0x1b1 [ 2.523309] [] ? irq_finalize_oneshot+0xc9/0xc9 [ 2.523314] [] kthread+0x7f/0x87 [ 2.523318] [] kernel_thread_helper+0x4/0x10 [ 2.523322] [] ? retint_restore_args+0xe/0xe [ 2.523326] [] ? __init_kthread_worker+0x55/0x55 [ 2.523330] [] ? gs_change+0xb/0xb [ 2.523409] [ 2.523409] =================================================== [ 2.523412] [ INFO: suspicious rcu_dereference_check() usage. ] [ 2.523414] --------------------------------------------------- [ 2.523416] kernel/sched.c:619 invoked rcu_dereference_check() without protection! [ 2.523418] [ 2.523419] other info that might help us debug this: [ 2.523420] [ 2.523422] [ 2.523422] rcu_scheduler_active = 1, debug_locks = 1 [ 2.523425] 2 locks held by irq/48-hda_inte/85: [ 2.523427] #0: (&rq->lock){-.-.-.}, at: [] double_rq_lock+0x62/0x77 [ 2.523434] #1: (&rq->lock/1){..-...}, at: [] double_rq_lock+0x6f/0x77 [ 2.523441] [ 2.523442] stack backtrace: [ 2.523444] Pid: 85, comm: irq/48-hda_inte Not tainted 2.6.39-rc7-mmotm0512 #2 [ 2.523446] Call Trace: [ 2.523450] [] lockdep_rcu_dereference+0x9a/0xa2 [ 2.523454] [] task_group+0x7a/0xb9 [ 2.523458] [] set_task_rq+0x12/0x6b [ 2.523462] [] set_task_cpu+0x8b/0xe8 [ 2.523466] [] ? plist_check_head+0x120/0x125 [ 2.523470] [] ? plist_del+0x70/0x79 [ 2.523474] [] ? dequeue_task_rt+0x33/0x38 [ 2.523477] [] ? dequeue_task+0x9b/0xa7 [ 2.523482] [] push_rt_task.part.60+0x11c/0x156 [ 2.523486] [] post_schedule_rt+0x1a/0x23 [ 2.523489] [] post_schedule.part.20+0x2b/0x45 [ 2.523494] [] schedule+0x6f2/0x738 [ 2.523497] [] ? irq_thread_fn+0x29/0x29 [ 2.523501] [] irq_thread+0x173/0x1b1 [ 2.523505] [] ? irq_finalize_oneshot+0xc9/0xc9 [ 2.523509] [] kthread+0x7f/0x87 [ 2.523513] [] kernel_thread_helper+0x4/0x10 [ 2.523517] [] ? retint_restore_args+0xe/0xe [ 2.523521] [] ? __init_kthread_worker+0x55/0x55 [ 2.523524] [] ? gs_change+0xb/0xb [ 2.548750] input: HDA Intel Mic at Sep Left Jack as /devices/pci0000:00/0000:00:1b.0/sound/card0/input6 --==_Exmh_1306275571_2633P Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (GNU/Linux) Comment: Exmh version 2.5 07/13/2001 iD8DBQFN3C7zcC3lWbTT17ARAjuLAJ9nHY1ILq7LuBy5o6wKQLV4S4hLjQCg5nBW DALdy6p+cPsiuZKav1wo3bs= =6/N7 -----END PGP SIGNATURE----- --==_Exmh_1306275571_2633P--