Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762197AbXFGO1U (ORCPT ); Thu, 7 Jun 2007 10:27:20 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754634AbXFGO1N (ORCPT ); Thu, 7 Jun 2007 10:27:13 -0400 Received: from nz-out-0506.google.com ([64.233.162.234]:18432 "EHLO nz-out-0506.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752310AbXFGO1M (ORCPT ); Thu, 7 Jun 2007 10:27:12 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=beta; h=received:message-id:date:from:to:subject:mime-version:content-type:content-transfer-encoding:content-disposition; b=mySJpA98S1Er+x+TzR2hLsi/NfHjhAQf15t+veQLrzrp/iGIvC8PcoQvBSz4Cu3PWY14CVGO/txNW+33Y8q/s8UrA/+tAe0o6qashWJQzFeeGjAM2UkKzdXkgF6uWkMsjJv3Uzw9I6vFxNnZ3etMtGfAaswAB95r2xZPQwYxGpc= Message-ID: <4bacf17f0706070727x3714fe68n19d0fa59a4dacc79@mail.gmail.com> Date: Thu, 7 Jun 2007 16:27:06 +0200 From: "=?ISO-8859-2?Q?Marcin_=A6lusarz?=" To: mchehab@infradead.org, video4linux-list@redhat.com, linux-kernel@vger.kernel.org Subject: bttv on 2.6.21.3: possible circular locking dependency detected MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6286 Lines: 115 [ 170.012538] [ 170.012540] ======================================================= [ 170.012545] [ INFO: possible circular locking dependency detected ] [ 170.012547] 2.6.21.3 #1 [ 170.012549] ------------------------------------------------------- [ 170.012551] tvtime/6727 is trying to acquire lock: [ 170.012554] (&mm->mmap_sem){----}, at: [] videobuf_dma_init_user+0xd4/0x180 [video_buf] [ 170.012564] [ 170.012565] but task is already holding lock: [ 170.012567] (&q->lock#2){--..}, at: [] mutex_lock+0x9/0x10 [ 170.012575] [ 170.012576] which lock already depends on the new lock. [ 170.012577] [ 170.012579] [ 170.012579] the existing dependency chain (in reverse order) is: [ 170.012581] [ 170.012582] -> #1 (&q->lock#2){--..}: [ 170.012585] [] __lock_acquire+0xc82/0xf30 [ 170.012593] [] bttv_do_ioctl+0x152f/0x2460 [bttv] [ 170.012608] [] mutex_lock+0x9/0x10 [ 170.012615] [] lock_acquire+0x88/0xc0 [ 170.012621] [] mutex_lock+0x9/0x10 [ 170.012627] [] __mutex_lock_slowpath+0xec/0x2a0 [ 170.012634] [] check_poison_obj+0x31/0x1f0 [ 170.012640] [] kmem_cache_zalloc+0x8b/0xe0 [ 170.012647] [] mutex_lock+0x9/0x10 [ 170.012653] [] videobuf_mmap_mapper+0x1c/0x290 [video_buf] [ 170.012662] [] bttv_mmap+0x5b/0x60 [bttv] [ 170.012673] [] do_mmap_pgoff+0x4e3/0x800 [ 170.012679] [] _spin_unlock_irq+0x2b/0x60 [ 170.012685] [] sys_mmap+0x9b/0x130 [ 170.012691] [] system_call+0x7e/0x83 [ 170.012697] [] 0xffffffffffffffff [ 170.012727] [ 170.012728] -> #0 (&mm->mmap_sem){----}: [ 170.012731] [] __lock_acquire+0xb3e/0xf30 [ 170.012737] [] videobuf_dma_init_user+0xd4/0x180 [video_buf] [ 170.012745] [] lock_acquire+0x88/0xc0 [ 170.012751] [] videobuf_dma_init_user+0xd4/0x180 [video_buf] [ 170.012760] [] down_read+0x28/0x40 [ 170.012765] [] videobuf_dma_init_user+0xd4/0x180 [video_buf] [ 170.012774] [] trace_hardirqs_on+0x14b/0x180 [ 170.012780] [] videobuf_iolock+0x9c/0x100 [video_buf] [ 170.012788] [] bttv_prepare_buffer+0x2ae/0x310 [bttv] [ 170.012800] [] buffer_prepare+0x32/0x40 [bttv] [ 170.012811] [] mutex_lock+0x9/0x10 [ 170.012818] [] videobuf_qbuf+0x2ea/0x3a0 [video_buf] [ 170.012826] [] bttv_do_ioctl+0x156b/0x2460 [bttv] [ 170.012838] [] __lock_acquire+0xe99/0xf30 [ 170.012844] [] __handle_mm_fault+0xb45/0xb80 [ 170.012850] [] __up_read+0x2a/0xa0 [ 170.012856] [] video_usercopy+0x189/0x250 [videodev] [ 170.012865] [] bttv_do_ioctl+0x0/0x2460 [bttv] [ 170.012877] [] do_page_fault+0x4bb/0x8f0 [ 170.012883] [] __up_write+0xfa/0x110 [ 170.012889] [] _spin_unlock_irqrestore+0x45/0x80 [ 170.012895] [] bttv_ioctl+0x6f/0x80 [bttv] [ 170.012907] [] do_ioctl+0x6b/0xa0 [ 170.012913] [] vfs_ioctl+0x2ab/0x2d0 [ 170.012919] [] sys_ioctl+0x4a/0x80 [ 170.012925] [] system_call+0x7e/0x83 [ 170.012931] [] 0xffffffffffffffff [ 170.012937] [ 170.012938] other info that might help us debug this: [ 170.012939] [ 170.012941] 1 lock held by tvtime/6727: [ 170.012943] #0: (&q->lock#2){--..}, at: [] mutex_lock+0x9/0x10 [ 170.012950] [ 170.012950] stack backtrace: [ 170.012952] [ 170.012953] Call Trace: [ 170.012957] [] print_circular_bug_tail+0x76/0x90 [ 170.012962] [] __lock_acquire+0xb3e/0xf30 [ 170.012969] [] :video_buf:videobuf_dma_init_user+0xd4/0x180 [ 170.012974] [] lock_acquire+0x88/0xc0 [ 170.012979] [] :video_buf:videobuf_dma_init_user+0xd4/0x180 [ 170.012984] [] down_read+0x28/0x40 [ 170.012989] [] :video_buf:videobuf_dma_init_user+0xd4/0x180 [ 170.012993] [] trace_hardirqs_on+0x14b/0x180 [ 170.013000] [] :video_buf:videobuf_iolock+0x9c/0x100 [ 170.013010] [] :bttv:bttv_prepare_buffer+0x2ae/0x310 [ 170.013021] [] :bttv:buffer_prepare+0x32/0x40 [ 170.013025] [] mutex_lock+0x9/0x10 [ 170.013030] [] :video_buf:videobuf_qbuf+0x2ea/0x3a0 [ 170.013041] [] :bttv:bttv_do_ioctl+0x156b/0x2460 [ 170.013045] [] __lock_acquire+0xe99/0xf30 [ 170.013049] [] __handle_mm_fault+0xb45/0xb80 [ 170.013054] [] __up_read+0x2a/0xa0 [ 170.013060] [] :videodev:video_usercopy+0x189/0x250 [ 170.013069] [] :bttv:bttv_do_ioctl+0x0/0x2460 [ 170.013075] [] do_page_fault+0x4bb/0x8f0 [ 170.013079] [] __up_write+0xfa/0x110 [ 170.013082] [] _spin_unlock_irqrestore+0x45/0x80 [ 170.013093] [] :bttv:bttv_ioctl+0x6f/0x80 [ 170.013097] [] do_ioctl+0x6b/0xa0 [ 170.013101] [] vfs_ioctl+0x2ab/0x2d0 [ 170.013105] [] sys_ioctl+0x4a/0x80 [ 170.013110] [] system_call+0x7e/0x83 [ 170.013113] - 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/