From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755155AbYIKSVk (ORCPT ); Thu, 11 Sep 2008 14:21:40 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751848AbYIKSVc (ORCPT ); Thu, 11 Sep 2008 14:21:32 -0400 Received: from main.gmane.org ([80.91.229.2]:44920 "EHLO ciao.gmane.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751167AbYIKSVb (ORCPT ); Thu, 11 Sep 2008 14:21:31 -0400 X-Injected-Via-Gmane: http://gmane.org/ To: linux-kernel@vger.kernel.org From: Marcus Furlong Subject: Re: 2.6.26.4 hard-unsafe lock order detected (drm-related?) Date: Thu, 11 Sep 2008 19:21:24 +0100 Message-ID: References: <1221070510.4415.207.camel@twins.programming.kicks-ass.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7Bit X-Complaints-To: usenet@ger.gmane.org X-Gmane-NNTP-Posting-Host: 84-203-83-149.mysmart.ie User-Agent: KNode/0.10.9 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thursday 11 September 2008 12:36 in , Marcus Furlong wrote: > On Wednesday 10 September 2008 19:15 in > <1221070510.4415.207.camel@twins.programming.kicks-ass.net>, Peter Zijlstra > wrote: > >> On Wed, 2008-09-10 at 17:48 +0100, Marcus Furlong wrote: >>> Hi, >>> >>> Just found this in dmesg, if any more info is needed let me know. >> >> Dave, have you ever seen this one before? >> >> Marcus, can you reproduce? - if so, could you try .27-rc6 to see if it >> is still valid? > > Can't reproduce so far. Actually just found another one on 2.6.26.4. Not sure what I was doing at the time though. Tried 27-rc6 for a few hours last night and it didn't recoccur. I'll see if I can pinpoint what causes it. [16869.930402] ====================================================== [16869.930413] [ INFO: hard-safe -> hard-unsafe lock order detected ] [16869.930418] 2.6.26.4 #1 [16869.930422] ------------------------------------------------------ [16869.930427] swapper/0 [HC0[0]:SC1[2]:HE0:SE0] is trying to acquire: [16869.930432] (&dev->lock.spinlock){-+..}, at: [] drm_lock_take+0x1c/0xc0 [drm] [16869.930460] [16869.930461] and this task is already holding: [16869.930464] (&dev->tasklet_lock){++..}, at: [] drm_locked_tasklet_func+0x1e/0x90 [drm] [16869.930485] which would create a new lock dependency: [16869.930490] (&dev->tasklet_lock){++..} -> (&dev->lock.spinlock){-+..} [16869.930510] [16869.930511] but this new dependency connects a hard-irq-safe lock: [16869.930517] (&dev->tasklet_lock){++..} [16869.930524] ... which became hard-irq-safe at: [16869.930529] [] __lock_acquire+0x82d/0xfb0 [16869.930544] [] lock_acquire+0x61/0x80 [16869.930556] [] _spin_lock_irqsave+0x43/0x60 [16869.930571] [] drm_locked_tasklet+0x4d/0xa0 [drm] [16869.930592] [] i915_driver_irq_handler+0x1c3/0x1f0 [i915] [16869.930611] [] handle_IRQ_event+0x28/0x60 [16869.930624] [] handle_fasteoi_irq+0x78/0xf0 [16869.930636] [] do_IRQ+0x79/0xc0 [16869.930649] [] 0xffffffff [16869.930661] [16869.930662] to a hard-irq-unsafe lock: [16869.930668] (&dev->lock.spinlock){-+..} [16869.930674] ... which became hard-irq-unsafe at: [16869.930679] ... [] __lock_acquire+0x606/0xfb0 [16869.930696] [] lock_acquire+0x61/0x80 [16869.930708] [] _spin_lock_bh+0x3b/0x50 [16869.930724] [] drm_lock+0x8e/0x310 [drm] [16869.930747] [] drm_ioctl+0x1b9/0x2f0 [drm] [16869.930773] [] vfs_ioctl+0x6b/0x80 [16869.930785] [] do_vfs_ioctl+0x57/0x2b0 [16869.930798] [] sys_ioctl+0x39/0x60 [16869.930809] [] sysenter_past_esp+0x6a/0xb1 [16869.930821] [] 0xffffffff [16869.930837] [16869.930838] other info that might help us debug this: [16869.930839] [16869.930842] 1 lock held by swapper/0: [16869.930844] #0: (&dev->tasklet_lock){++..}, at: [] drm_locked_tasklet_func+0x1e/0x90 [drm] [16869.930858] [16869.930859] the hard-irq-safe lock's dependencies: [16869.930862] -> (&dev->tasklet_lock){++..} ops: 0 { [16869.930870] initial-use at: [16869.930873] [] __lock_acquire+0x11d/0xfb0 [16869.930932] [] lock_acquire+0x61/0x80 [16869.930987] [] _spin_lock_irqsave+0x43/0x60 [16869.930987] [] drm_unlock+0x27/0xc0 [drm] [16869.930987] [] drm_ioctl+0x1b9/0x2f0 [drm] [16869.930987] [] vfs_ioctl+0x6b/0x80 [16869.930987] [] do_vfs_ioctl+0x57/0x2b0 [16869.930987] [] sys_ioctl+0x39/0x60 [16869.930987] [] sysenter_past_esp+0x6a/0xb1 [16869.930987] [] 0xffffffff [16869.930987] in-hardirq-W at: [16869.930987] [] __lock_acquire+0x82d/0xfb0 [16869.930987] [] lock_acquire+0x61/0x80 [16869.930987] [] _spin_lock_irqsave+0x43/0x60 [16869.930987] [] drm_locked_tasklet+0x4d/0xa0 [drm] [16869.930987] [] i915_driver_irq_handler+0x1c3/0x1f0 [i915] [16869.930987] [] handle_IRQ_event+0x28/0x60 [16869.930987] [] handle_fasteoi_irq+0x78/0xf0 [16869.930987] [] do_IRQ+0x79/0xc0 [16869.930987] [] 0xffffffff [16869.930987] in-softirq-W at: [16869.930987] [] __lock_acquire+0x4bf/0xfb0 [16869.930987] [] lock_acquire+0x61/0x80 [16869.930987] [] _spin_lock_irqsave+0x43/0x60 [16869.930987] [] drm_locked_tasklet_func+0x1e/0x90 [drm] [16869.930987] [] tasklet_hi_action+0x5b/0xd0 [16869.930987] [] __do_softirq+0x74/0xe0 [16869.930987] [] do_softirq+0x95/0xd0 [16869.930987] [] 0xffffffff [16869.930987] } [16869.930987] ... key at: [] __key.23164+0x0/0xffff90cb [drm] [16869.930987] [16869.930987] the hard-irq-unsafe lock's dependencies: [16869.930987] -> (&dev->lock.spinlock){-+..} ops: 0 { [16869.930987] initial-use at: [16869.930987] [] __lock_acquire+0x11d/0xfb0 [16869.930987] [] lock_acquire+0x61/0x80 [16869.930987] [] _spin_lock_bh+0x3b/0x50 [16869.930987] [] drm_lock+0x8e/0x310 [drm] [16869.930987] [] drm_ioctl+0x1b9/0x2f0 [drm] [16869.930987] [] vfs_ioctl+0x6b/0x80 [16869.930987] [] do_vfs_ioctl+0x57/0x2b0 [16869.930987] [] sys_ioctl+0x39/0x60 [16869.930987] [] sysenter_past_esp+0x6a/0xb1 [16869.930987] [] 0xffffffff [16869.930987] in-softirq-W at: [16869.930987] [] __lock_acquire+0x4bf/0xfb0 [16869.930987] [] lock_acquire+0x61/0x80 [16869.930987] [] _spin_lock_bh+0x3b/0x50 [16869.930987] [] drm_lock_take+0x1c/0xc0 [drm] [16869.930987] [] drm_locked_tasklet_func+0x3a/0x90 [drm] [16869.930987] [] tasklet_hi_action+0x5b/0xd0 [16869.930987] [] __do_softirq+0x74/0xe0 [16869.930987] [] do_softirq+0x95/0xd0 [16869.930987] [] 0xffffffff [16869.930987] hardirq-on-W at: [16869.930987] [] __lock_acquire+0x606/0xfb0 [16869.930987] [] lock_acquire+0x61/0x80 [16869.930987] [] _spin_lock_bh+0x3b/0x50 [16869.930987] [] drm_lock+0x8e/0x310 [drm] [16869.930987] [] drm_ioctl+0x1b9/0x2f0 [drm] [16869.930987] [] vfs_ioctl+0x6b/0x80 [16869.930987] [] do_vfs_ioctl+0x57/0x2b0 [16869.930987] [] sys_ioctl+0x39/0x60 [16869.930987] [] sysenter_past_esp+0x6a/0xb1 [16869.930987] [] 0xffffffff [16869.930987] } [16869.930987] ... key at: [] __key.23165+0x0/0xffff90d3 [drm] [16869.930987] [16869.930987] stack backtrace: [16869.930987] Pid: 0, comm: swapper Not tainted 2.6.26.4 #1 [16869.930987] [] check_usage+0x252/0x260 [16869.930987] [] __lock_acquire+0xae8/0xfb0 [16869.930987] [] ? hrtick_start_fair+0x114/0x170 [16869.930987] [] lock_acquire+0x61/0x80 [16869.930987] [] ? drm_lock_take+0x1c/0xc0 [drm] [16869.930987] [] _spin_lock_bh+0x3b/0x50 [16869.930987] [] ? drm_lock_take+0x1c/0xc0 [drm] [16869.930987] [] drm_lock_take+0x1c/0xc0 [drm] [16869.930987] [] drm_locked_tasklet_func+0x3a/0x90 [drm] [16869.930987] [] tasklet_hi_action+0x5b/0xd0 [16869.930987] [] __do_softirq+0x74/0xe0 [16869.930987] [] do_softirq+0x95/0xd0 [16869.930987] [] ? handle_fasteoi_irq+0x0/0xf0 [16869.930987] [] irq_exit+0x86/0xa0 [16869.930987] [] do_IRQ+0x80/0xc0 [16869.930987] [] common_interrupt+0x2e/0x34 [16869.930987] [] ? tick_setup_oneshot+0x28/0x40 [16869.930987] [] ? acpi_idle_enter_bm+0x297/0x306 [16869.930987] [] cpuidle_idle_call+0x6b/0xc0 [16869.930987] [] ? cpuidle_idle_call+0x0/0xc0 [16869.930987] [] cpu_idle+0x60/0xf0 [16869.930987] [] rest_init+0x62/0x70 [16869.930987] =======================