Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753057AbbG3QAd (ORCPT ); Thu, 30 Jul 2015 12:00:33 -0400 Received: from mail-wi0-f169.google.com ([209.85.212.169]:35635 "EHLO mail-wi0-f169.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753004AbbG3QAb (ORCPT ); Thu, 30 Jul 2015 12:00:31 -0400 Date: Thu, 30 Jul 2015 18:00:26 +0200 From: Daniel Vetter To: "Theodore Ts'o" , Linus Torvalds , intel-gfx , DRI , Daniel Vetter , Mani Nikula , Ander Conselvan de Oliveira , Linux Kernel Mailing List Subject: Re: [REGRESSION] Re: i915 driver crashes on T540p if docking station attached Message-ID: <20150730160026.GC16722@phenom.ffwll.local> Mail-Followup-To: Theodore Ts'o , Linus Torvalds , intel-gfx , DRI , Daniel Vetter , Mani Nikula , Ander Conselvan de Oliveira , Linux Kernel Mailing List References: <20150730004937.GA3133@thunk.org> <20150730013912.GA4068@thunk.org> <20150730144002.GY16722@phenom.ffwll.local> <20150730155029.GA3065@thunk.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20150730155029.GA3065@thunk.org> X-Operating-System: Linux phenom 4.2.0-rc1+ User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 15119 Lines: 184 On Thu, Jul 30, 2015 at 11:50:29AM -0400, Theodore Ts'o wrote: > On Thu, Jul 30, 2015 at 04:40:02PM +0200, Daniel Vetter wrote: > > I have 4 patches in git://people.freedesktop.org/~danvet/drm fixes-stuff > > but I couldn't test them yet since no dp mst here and I didn't find > > anything that would ship faster than 1-2 weeks yet. I'll try to get some > > other people here to test it meanwhile too. > > I've tried pulling in your patches from fixes-stuff, onto Linus's tree > (without Linus's fix), and the good news is that I'm no longer > crashing on boot. Ok so I'm not completely clueless yet, the encoder confusion indeed resulted in the follow-up crash. But obviously I don't understand yet exactly what's going on if this breaks the display. > The *bad* news is that (a) it breaks the external monitor attached to > the docking station completely (this was working with Linus's patch), > and (b) it's triggering a LOCKDEP failure. The lockdep splat is all in the driver load before we do any modeset at all, so shouldn't have changed between these patches. Are you sure it's a regression due to mine and wasn't there before? > So even though Linus's patch wasn't supposed to work, I think I'm > going to back to it.... Well I found some dp mst hubs meanwhile so hopefully tomorrow I can test myself what's going wrong here. -Daniel > > - Ted > > > Jul 30 11:46:49 closure kernel: [ 4.221951] > Jul 30 11:46:49 closure kernel: [ 4.221954] ====================================================== > Jul 30 11:46:49 closure kernel: [ 4.221957] [ INFO: possible circular locking dependency detected ] > Jul 30 11:46:49 closure kernel: [ 4.221960] 4.2.0-rc4-13906-g5f1b75cd #16 Not tainted > Jul 30 11:46:49 closure kernel: [ 4.221963] ------------------------------------------------------- > Jul 30 11:46:49 closure kernel: [ 4.221966] modprobe/503 is trying to acquire lock: > Jul 30 11:46:49 closure kernel: [ 4.221968] (init_mutex){+.+.+.}, at: [] acpi_video_get_backlight_type+0x17/0x164 > Jul 30 11:46:49 closure kernel: [ 4.221977] > Jul 30 11:46:49 closure kernel: [ 4.221977] but task is already holding lock: > Jul 30 11:46:49 closure kernel: [ 4.221979] (&(&backlight_notifier)->rwsem){++++..}, at: [] __blocking_notifier_call_chain+0x37/0x69 > Jul 30 11:46:49 closure kernel: [ 4.221987] > Jul 30 11:46:49 closure kernel: [ 4.221987] which lock already depends on the new lock. > Jul 30 11:46:49 closure kernel: [ 4.221987] > Jul 30 11:46:49 closure kernel: [ 4.221990] > Jul 30 11:46:49 closure kernel: [ 4.221990] the existing dependency chain (in reverse order) is: > Jul 30 11:46:49 closure kernel: [ 4.221995] > Jul 30 11:46:49 closure kernel: [ 4.221995] -> #1 (&(&backlight_notifier)->rwsem){++++..}: > Jul 30 11:46:49 closure kernel: [ 4.222001] [] lock_acquire+0x104/0x18b > Jul 30 11:46:49 closure kernel: [ 4.222007] [] down_write+0x46/0x8a > Jul 30 11:46:49 closure kernel: [ 4.222012] [] blocking_notifier_chain_register+0x36/0x57 > Jul 30 11:46:49 closure kernel: [ 4.222017] [] backlight_register_notifier+0x18/0x1a > Jul 30 11:46:49 closure kernel: [ 4.222022] [] acpi_video_get_backlight_type+0xfa/0x164 > Jul 30 11:46:49 closure kernel: [ 4.222028] [] 0xffffffffc03a1e45 > Jul 30 11:46:49 closure audispd: No plugins found, exiting > Jul 30 11:46:49 closure kernel: [ 4.222032] [] 0xffffffffc03a28a8 > Jul 30 11:46:49 closure kernel: [ 4.222036] [] do_one_initcall+0x19a/0x1af > Jul 30 11:46:49 closure kernel: [ 4.222042] [] do_init_module+0x60/0x1e3 > Jul 30 11:46:49 closure kernel: [ 4.222047] [] load_module+0x1c42/0x2059 > Jul 30 11:46:49 closure kernel: [ 4.222052] [] SyS_finit_module+0x85/0x92 > Jul 30 11:46:49 closure kernel: [ 4.222056] [] entry_SYSCALL_64_fastpath+0x16/0x73 > Jul 30 11:46:49 closure kernel: [ 4.222060] > Jul 30 11:46:49 closure kernel: [ 4.222060] -> #0 (init_mutex){+.+.+.}: > Jul 30 11:46:49 closure kernel: [ 4.222065] [] __lock_acquire+0xc55/0xf54 > Jul 30 11:46:49 closure kernel: [ 4.222070] [] lock_acquire+0x104/0x18b > Jul 30 11:46:49 closure kernel: [ 4.222074] [] mutex_lock_nested+0x70/0x391 > Jul 30 11:46:49 closure kernel: [ 4.222078] [] acpi_video_get_backlight_type+0x17/0x164 > Jul 30 11:46:49 closure kernel: [ 4.222083] [] acpi_video_backlight_notify+0x19/0x2f > Jul 30 11:46:49 closure kernel: [ 4.222088] [] notifier_call_chain+0x4c/0x71 > Jul 30 11:46:49 closure kernel: [ 4.222092] [] __blocking_notifier_call_chain+0x50/0x69 > Jul 30 11:46:49 closure kernel: [ 4.222098] [] blocking_notifier_call_chain+0x14/0x16 > Jul 30 11:46:49 closure kernel: [ 4.222103] [] backlight_device_register+0x1df/0x1f1 > Jul 30 11:46:49 closure kernel: [ 4.222108] [] intel_backlight_register+0xf0/0x157 [i915] > Jul 30 11:46:49 closure kernel: [ 4.222146] [] intel_modeset_gem_init+0x158/0x164 [i915] > Jul 30 11:46:49 closure kernel: [ 4.222176] [] i915_driver_load+0xf1c/0x1139 [i915] > Jul 30 11:46:49 closure kernel: [ 4.222205] [] drm_dev_register+0x84/0xfd [drm] > Jul 30 11:46:49 closure kernel: [ 4.222217] [] drm_get_pci_dev+0x102/0x1bc [drm] > Jul 30 11:46:49 closure kernel: [ 4.222228] [] i915_pci_probe+0x4f/0x51 [i915] > Jul 30 11:46:49 closure kernel: [ 4.222247] [] pci_device_probe+0x74/0xd6 > Jul 30 11:46:49 closure kernel: [ 4.222253] [] driver_probe_device+0x15f/0x387 > Jul 30 11:46:49 closure kernel: [ 4.222257] [] __driver_attach+0x53/0x74 > Jul 30 11:46:49 closure kernel: [ 4.222262] [] bus_for_each_dev+0x6f/0x89 > Jul 30 11:46:49 closure kernel: [ 4.222266] [] driver_attach+0x1e/0x20 > Jul 30 11:46:49 closure kernel: [ 4.222269] [] bus_add_driver+0x140/0x238 > Jul 30 11:46:49 closure kernel: [ 4.222273] [] driver_register+0x8f/0xcc > Jul 30 11:46:49 closure kernel: [ 4.222278] [] __pci_register_driver+0x5e/0x62 > Jul 30 11:46:49 closure kernel: [ 4.222282] [] drm_pci_init+0x58/0xda [drm] > Jul 30 11:46:49 closure kernel: [ 4.222293] [] i915_init+0xa0/0xa8 [i915] > Jul 30 11:46:49 closure kernel: [ 4.222312] [] do_one_initcall+0x19a/0x1af > Jul 30 11:46:49 closure kernel: [ 4.222317] [] do_init_module+0x60/0x1e3 > Jul 30 11:46:49 closure kernel: [ 4.222321] [] load_module+0x1c42/0x2059 > Jul 30 11:46:49 closure kernel: [ 4.222325] [] SyS_finit_module+0x85/0x92 > Jul 30 11:46:49 closure kernel: [ 4.222329] [] entry_SYSCALL_64_fastpath+0x16/0x73 > Jul 30 11:46:49 closure kernel: [ 4.222334] > Jul 30 11:46:49 closure kernel: [ 4.222334] other info that might help us debug this: > Jul 30 11:46:49 closure kernel: [ 4.222334] > Jul 30 11:46:49 closure kernel: [ 4.222340] Possible unsafe locking scenario: > Jul 30 11:46:49 closure kernel: [ 4.222340] > Jul 30 11:46:49 closure kernel: [ 4.222344] CPU0 CPU1 > Jul 30 11:46:49 closure kernel: [ 4.222347] ---- ---- > Jul 30 11:46:49 closure kernel: [ 4.222350] lock(&(&backlight_notifier)->rwsem); > Jul 30 11:46:49 closure kernel: [ 4.222353] lock(init_mutex); > Jul 30 11:46:49 closure kernel: [ 4.222357] lock(&(&backlight_notifier)->rwsem); > Jul 30 11:46:49 closure kernel: [ 4.222363] lock(init_mutex); > Jul 30 11:46:49 closure kernel: [ 4.222366] > Jul 30 11:46:49 closure kernel: [ 4.222366] *** DEADLOCK *** > Jul 30 11:46:49 closure kernel: [ 4.222366] > Jul 30 11:46:49 closure kernel: [ 4.222371] 4 locks held by modprobe/503: > Jul 30 11:46:49 closure kernel: [ 4.222374] #0: (&dev->mutex){......}, at: [] device_lock+0xf/0x11 > Jul 30 11:46:49 closure kernel: [ 4.222381] #1: (&dev->mutex){......}, at: [] device_lock+0xf/0x11 > Jul 30 11:46:49 closure kernel: [ 4.222388] #2: (drm_global_mutex){+.+.+.}, at: [] drm_dev_register+0x24/0xfd [drm] > Jul 30 11:46:49 closure kernel: [ 4.222402] #3: (&(&backlight_notifier)->rwsem){++++..}, at: [] __blocking_notifier_call_chain+0x37/0x69 > Jul 30 11:46:49 closure kernel: [ 4.222410] > Jul 30 11:46:49 closure kernel: [ 4.222410] stack backtrace: > Jul 30 11:46:49 closure kernel: [ 4.222416] CPU: 7 PID: 503 Comm: modprobe Not tainted 4.2.0-rc4-13906-g5f1b75cd #16 > Jul 30 11:46:49 closure kernel: [ 4.222420] Hardware name: LENOVO 20BECTO1WW/20BECTO1WW, BIOS GMET59WW (2.07 ) 02/12/2014 > Jul 30 11:46:49 closure kernel: [ 4.222425] ffffffff8280a230 ffff8800c992b5d8 ffffffff8161a71e 0000000000000006 > Jul 30 11:46:49 closure kernel: [ 4.222431] ffffffff8280a230 ffff8800c992b628 ffffffff810b9adf ffffffff82265780 > Jul 30 11:46:49 closure kernel: [ 4.222437] ffff880405588000 0000000000000004 ffff880405588880 0000000000000004 > Jul 30 11:46:49 closure kernel: [ 4.222443] Call Trace: > Jul 30 11:46:49 closure kernel: [ 4.222447] [] dump_stack+0x4c/0x65 > Jul 30 11:46:49 closure kernel: [ 4.222451] [] print_circular_bug+0x1f8/0x209 > Jul 30 11:46:49 closure kernel: [ 4.222455] [] __lock_acquire+0xc55/0xf54 > Jul 30 11:46:49 closure kernel: [ 4.222460] [] lock_acquire+0x104/0x18b > Jul 30 11:46:49 closure kernel: [ 4.222464] [] ? acpi_video_get_backlight_type+0x17/0x164 > Jul 30 11:46:49 closure kernel: [ 4.222469] [] mutex_lock_nested+0x70/0x391 > Jul 30 11:46:49 closure kernel: [ 4.222472] [] ? acpi_video_get_backlight_type+0x17/0x164 > Jul 30 11:46:49 closure kernel: [ 4.222476] [] ? acpi_video_get_backlight_type+0x17/0x164 > Jul 30 11:46:49 closure kernel: [ 4.222480] [] acpi_video_get_backlight_type+0x17/0x164 > Jul 30 11:46:49 closure kernel: [ 4.222484] [] acpi_video_backlight_notify+0x19/0x2f > Jul 30 11:46:49 closure kernel: [ 4.222488] [] notifier_call_chain+0x4c/0x71 > Jul 30 11:46:49 closure kernel: [ 4.222492] [] __blocking_notifier_call_chain+0x50/0x69 > Jul 30 11:46:49 closure kernel: [ 4.222496] [] blocking_notifier_call_chain+0x14/0x16 > Jul 30 11:46:49 closure kernel: [ 4.222500] [] backlight_device_register+0x1df/0x1f1 > Jul 30 11:46:49 closure kernel: [ 4.222530] [] intel_backlight_register+0xf0/0x157 [i915] > Jul 30 11:46:49 closure kernel: [ 4.222556] [] intel_modeset_gem_init+0x158/0x164 [i915] > Jul 30 11:46:49 closure kernel: [ 4.222584] [] i915_driver_load+0xf1c/0x1139 [i915] > Jul 30 11:46:49 closure kernel: [ 4.222589] [] ? mark_held_locks+0x56/0x6c > Jul 30 11:46:49 closure kernel: [ 4.222593] [] ? _raw_spin_unlock_irqrestore+0x3f/0x4d > Jul 30 11:46:49 closure kernel: [ 4.222597] [] ? trace_hardirqs_on_caller+0x171/0x18d > Jul 30 11:46:49 closure kernel: [ 4.222607] [] drm_dev_register+0x84/0xfd [drm] > Jul 30 11:46:49 closure kernel: [ 4.222618] [] drm_get_pci_dev+0x102/0x1bc [drm] > Jul 30 11:46:49 closure kernel: [ 4.222636] [] i915_pci_probe+0x4f/0x51 [i915] > Jul 30 11:46:49 closure kernel: [ 4.222640] [] pci_device_probe+0x74/0xd6 > Jul 30 11:46:49 closure kernel: [ 4.222644] [] ? driver_probe_device+0x387/0x387 > Jul 30 11:46:49 closure kernel: [ 4.222648] [] driver_probe_device+0x15f/0x387 > Jul 30 11:46:49 closure kernel: [ 4.222652] [] ? driver_probe_device+0x387/0x387 > Jul 30 11:46:49 closure kernel: [ 4.222655] [] __driver_attach+0x53/0x74 > Jul 30 11:46:49 closure kernel: [ 4.222659] [] bus_for_each_dev+0x6f/0x89 > Jul 30 11:46:49 closure kernel: [ 4.222662] [] driver_attach+0x1e/0x20 > Jul 30 11:46:49 closure kernel: [ 4.222666] [] bus_add_driver+0x140/0x238 > Jul 30 11:46:49 closure kernel: [ 4.222670] [] driver_register+0x8f/0xcc > Jul 30 11:46:49 closure kernel: [ 4.222674] [] __pci_register_driver+0x5e/0x62 > Jul 30 11:46:49 closure kernel: [ 4.222677] [] ? 0xffffffffc081f000 > Jul 30 11:46:49 closure kernel: [ 4.222687] [] drm_pci_init+0x58/0xda [drm] > Jul 30 11:46:49 closure kernel: [ 4.222690] [] ? 0xffffffffc081f000 > Jul 30 11:46:49 closure kernel: [ 4.222708] [] i915_init+0xa0/0xa8 [i915] > Jul 30 11:46:49 closure kernel: [ 4.222712] [] ? 0xffffffffc081f000 > Jul 30 11:46:49 closure kernel: [ 4.222716] [] do_one_initcall+0x19a/0x1af > Jul 30 11:46:49 closure kernel: [ 4.222719] [] ? do_init_module+0x28/0x1e3 > Jul 30 11:46:49 closure kernel: [ 4.222723] [] ? kmem_cache_alloc_trace+0xba/0xcc > Jul 30 11:46:49 closure kernel: [ 4.222727] [] do_init_module+0x60/0x1e3 > Jul 30 11:46:49 closure kernel: [ 4.222731] [] load_module+0x1c42/0x2059 > Jul 30 11:46:49 closure kernel: [ 4.222736] [] SyS_finit_module+0x85/0x92 > Jul 30 11:46:49 closure kernel: [ 4.222739] [] entry_SYSCALL_64_fastpath+0x16/0x73 > > > _______________________________________________ > dri-devel mailing list > dri-devel@lists.freedesktop.org > http://lists.freedesktop.org/mailman/listinfo/dri-devel -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/