bttv on 2.6.21.3: possible circular locking dependency detected
From: Marcin Ślusarz
Date: Thu Jun 07 2007 - 10:27:22 EST
[ 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: [<ffffffff88053cf4>]
videobuf_dma_init_user+0xd4/0x180 [video_buf]
[ 170.012564]
[ 170.012565] but task is already holding lock:
[ 170.012567] (&q->lock#2){--..}, at: [<ffffffff80267399>] 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] [<ffffffff802a6922>] __lock_acquire+0xc82/0xf30
[ 170.012593] [<ffffffff8805e86f>] bttv_do_ioctl+0x152f/0x2460 [bttv]
[ 170.012608] [<ffffffff80267399>] mutex_lock+0x9/0x10
[ 170.012615] [<ffffffff802a6c58>] lock_acquire+0x88/0xc0
[ 170.012621] [<ffffffff80267399>] mutex_lock+0x9/0x10
[ 170.012627] [<ffffffff802671dc>] __mutex_lock_slowpath+0xec/0x2a0
[ 170.012634] [<ffffffff80207131>] check_poison_obj+0x31/0x1f0
[ 170.012640] [<ffffffff802c979b>] kmem_cache_zalloc+0x8b/0xe0
[ 170.012647] [<ffffffff80267399>] mutex_lock+0x9/0x10
[ 170.012653] [<ffffffff880528bc>]
videobuf_mmap_mapper+0x1c/0x290 [video_buf]
[ 170.012662] [<ffffffff8805bfcb>] bttv_mmap+0x5b/0x60 [bttv]
[ 170.012673] [<ffffffff8020dc83>] do_mmap_pgoff+0x4e3/0x800
[ 170.012679] [<ffffffff8026921b>] _spin_unlock_irq+0x2b/0x60
[ 170.012685] [<ffffffff8022455b>] sys_mmap+0x9b/0x130
[ 170.012691] [<ffffffff8025f71e>] system_call+0x7e/0x83
[ 170.012697] [<ffffffffffffffff>] 0xffffffffffffffff
[ 170.012727]
[ 170.012728] -> #0 (&mm->mmap_sem){----}:
[ 170.012731] [<ffffffff802a67de>] __lock_acquire+0xb3e/0xf30
[ 170.012737] [<ffffffff88053cf4>]
videobuf_dma_init_user+0xd4/0x180 [video_buf]
[ 170.012745] [<ffffffff802a6c58>] lock_acquire+0x88/0xc0
[ 170.012751] [<ffffffff88053cf4>]
videobuf_dma_init_user+0xd4/0x180 [video_buf]
[ 170.012760] [<ffffffff802a1098>] down_read+0x28/0x40
[ 170.012765] [<ffffffff88053cf4>]
videobuf_dma_init_user+0xd4/0x180 [video_buf]
[ 170.012774] [<ffffffff802a572b>] trace_hardirqs_on+0x14b/0x180
[ 170.012780] [<ffffffff880540bc>] videobuf_iolock+0x9c/0x100
[video_buf]
[ 170.012788] [<ffffffff8805bece>]
bttv_prepare_buffer+0x2ae/0x310 [bttv]
[ 170.012800] [<ffffffff8805bf62>] buffer_prepare+0x32/0x40 [bttv]
[ 170.012811] [<ffffffff80267399>] mutex_lock+0x9/0x10
[ 170.012818] [<ffffffff880548ca>] videobuf_qbuf+0x2ea/0x3a0 [video_buf]
[ 170.012826] [<ffffffff8805e8ab>] bttv_do_ioctl+0x156b/0x2460 [bttv]
[ 170.012838] [<ffffffff802a6b39>] __lock_acquire+0xe99/0xf30
[ 170.012844] [<ffffffff80209225>] __handle_mm_fault+0xb45/0xb80
[ 170.012850] [<ffffffff80222b4a>] __up_read+0x2a/0xa0
[ 170.012856] [<ffffffff8802ec09>] video_usercopy+0x189/0x250 [videodev]
[ 170.012865] [<ffffffff8805d340>] bttv_do_ioctl+0x0/0x2460 [bttv]
[ 170.012877] [<ffffffff8026b8cb>] do_page_fault+0x4bb/0x8f0
[ 170.012883] [<ffffffff8023136a>] __up_write+0xfa/0x110
[ 170.012889] [<ffffffff802691b5>] _spin_unlock_irqrestore+0x45/0x80
[ 170.012895] [<ffffffff8805c0af>] bttv_ioctl+0x6f/0x80 [bttv]
[ 170.012907] [<ffffffff80242ebb>] do_ioctl+0x6b/0xa0
[ 170.012913] [<ffffffff8023124b>] vfs_ioctl+0x2ab/0x2d0
[ 170.012919] [<ffffffff8024de1a>] sys_ioctl+0x4a/0x80
[ 170.012925] [<ffffffff8025f71e>] system_call+0x7e/0x83
[ 170.012931] [<ffffffffffffffff>] 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: [<ffffffff80267399>]
mutex_lock+0x9/0x10
[ 170.012950]
[ 170.012950] stack backtrace:
[ 170.012952]
[ 170.012953] Call Trace:
[ 170.012957] [<ffffffff802a47a6>] print_circular_bug_tail+0x76/0x90
[ 170.012962] [<ffffffff802a67de>] __lock_acquire+0xb3e/0xf30
[ 170.012969] [<ffffffff88053cf4>]
:video_buf:videobuf_dma_init_user+0xd4/0x180
[ 170.012974] [<ffffffff802a6c58>] lock_acquire+0x88/0xc0
[ 170.012979] [<ffffffff88053cf4>]
:video_buf:videobuf_dma_init_user+0xd4/0x180
[ 170.012984] [<ffffffff802a1098>] down_read+0x28/0x40
[ 170.012989] [<ffffffff88053cf4>]
:video_buf:videobuf_dma_init_user+0xd4/0x180
[ 170.012993] [<ffffffff802a572b>] trace_hardirqs_on+0x14b/0x180
[ 170.013000] [<ffffffff880540bc>] :video_buf:videobuf_iolock+0x9c/0x100
[ 170.013010] [<ffffffff8805bece>] :bttv:bttv_prepare_buffer+0x2ae/0x310
[ 170.013021] [<ffffffff8805bf62>] :bttv:buffer_prepare+0x32/0x40
[ 170.013025] [<ffffffff80267399>] mutex_lock+0x9/0x10
[ 170.013030] [<ffffffff880548ca>] :video_buf:videobuf_qbuf+0x2ea/0x3a0
[ 170.013041] [<ffffffff8805e8ab>] :bttv:bttv_do_ioctl+0x156b/0x2460
[ 170.013045] [<ffffffff802a6b39>] __lock_acquire+0xe99/0xf30
[ 170.013049] [<ffffffff80209225>] __handle_mm_fault+0xb45/0xb80
[ 170.013054] [<ffffffff80222b4a>] __up_read+0x2a/0xa0
[ 170.013060] [<ffffffff8802ec09>] :videodev:video_usercopy+0x189/0x250
[ 170.013069] [<ffffffff8805d340>] :bttv:bttv_do_ioctl+0x0/0x2460
[ 170.013075] [<ffffffff8026b8cb>] do_page_fault+0x4bb/0x8f0
[ 170.013079] [<ffffffff8023136a>] __up_write+0xfa/0x110
[ 170.013082] [<ffffffff802691b5>] _spin_unlock_irqrestore+0x45/0x80
[ 170.013093] [<ffffffff8805c0af>] :bttv:bttv_ioctl+0x6f/0x80
[ 170.013097] [<ffffffff80242ebb>] do_ioctl+0x6b/0xa0
[ 170.013101] [<ffffffff8023124b>] vfs_ioctl+0x2ab/0x2d0
[ 170.013105] [<ffffffff8024de1a>] sys_ioctl+0x4a/0x80
[ 170.013110] [<ffffffff8025f71e>] 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@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/