[Bugme-new] [Bug 10838] New: possible circular locking dependency detected

bugme-daemon at bugzilla.kernel.org bugme-daemon at bugzilla.kernel.org
Fri May 30 11:51:27 PDT 2008 

http://bugzilla.kernel.org/show_bug.cgi?id=10838

           Summary: possible circular locking dependency detected
           Product: v4l-dvb
           Version: unspecified
     KernelVersion: 2.6.26-rc3-08493-gb8291ad-dirty
          Platform: All
        OS/Version: Linux
              Tree: Mainline
            Status: NEW
          Severity: normal
          Priority: P1
         Component: saa7134
        AssignedTo: v4l-dvb_saa7134 at kernel-bugs.osdl.org
        ReportedBy: stsp at aknet.ru


Latest working kernel version:
dont know

Earliest failing kernel version:
not sure, but seems rather recent

Distribution:
F9

Hardware Environment:
x86_64 PC

Software Environment:
xawtv and saa7134 driver

Problem Description:
May 30 18:44:49 lin2 kernel:
=======================================================
May 30 18:44:49 lin2 kernel: [ INFO: possible circular locking dependency
detected ]
May 30 18:44:49 lin2 kernel: 2.6.26-rc3-08493-gb8291ad-dirty #18
May 30 18:44:49 lin2 kernel:
-------------------------------------------------------
May 30 18:44:49 lin2 kernel: xawtv/3063 is trying to acquire lock:
May 30 18:44:49 lin2 kernel: (&mm->mmap_sem){----}, at: [<ffffffffa00d7d28>]
videobuf_dma_init_user+0x48/0xa0 [videobuf_dma_sg]
May 30 18:44:49 lin2 kernel: 
May 30 18:44:49 lin2 kernel: but task is already holding lock:
May 30 18:44:49 lin2 kernel: (&q->vb_lock){--..}, at: [<ffffffffa00c8f16>]
videobuf_read_one+0x46/0x458 [videobuf_core]
May 30 18:44:49 lin2 kernel: 
May 30 18:44:49 lin2 kernel: which lock already depends on the new lock.
May 30 18:44:49 lin2 kernel: 
May 30 18:44:49 lin2 kernel: 
May 30 18:44:49 lin2 kernel: the existing dependency chain (in reverse order)
is:
May 30 18:44:49 lin2 kernel: 
May 30 18:44:49 lin2 kernel: -> #1 (&q->vb_lock){--..}:
May 30 18:44:49 lin2 kernel: [<ffffffff8025e5b5>] add_lock_to_list+0x65/0xe0
May 30 18:44:49 lin2 kernel: [<ffffffff80260c70>] __lock_acquire+0xbc0/0x10a0
May 30 18:44:49 lin2 kernel: [<ffffffffa01190b0>] saa7134_querybuf+0x0/0x40
[saa7134]
May 30 18:44:49 lin2 kernel: [<ffffffffa00eff3b>]
__video_do_ioctl+0x1e0b/0x2ff0 [videodev]
May 30 18:44:49 lin2 kernel: [<ffffffffa00c7404>]
videobuf_mmap_mapper+0x24/0x70 [videobuf_core]
May 30 18:44:49 lin2 kernel: [<ffffffff802611a7>] lock_acquire+0x57/0x80
May 30 18:44:49 lin2 kernel: [<ffffffffa00c7404>]
videobuf_mmap_mapper+0x24/0x70 [videobuf_core]
May 30 18:44:49 lin2 kernel: [<ffffffff8050ce4a>] mutex_lock_nested+0xaa/0x310
May 30 18:44:49 lin2 kernel: [<ffffffff8025f7db>] mark_held_locks+0x5b/0xa0
May 30 18:44:49 lin2 kernel: [<ffffffff8025f9d7>] trace_hardirqs_on+0x117/0x160
May 30 18:44:49 lin2 kernel: [<ffffffffa00c7404>]
videobuf_mmap_mapper+0x24/0x70 [videobuf_core]
May 30 18:44:49 lin2 kernel: [<ffffffff8029c25c>] mmap_region+0x21c/0x580
May 30 18:44:49 lin2 kernel: [<ffffffff8029c8a4>] do_mmap_pgoff+0x2e4/0x3f0
May 30 18:44:49 lin2 kernel: [<ffffffff8050eaaf>] _spin_unlock_irq+0x2f/0x50
May 30 18:44:49 lin2 kernel: [<ffffffff802109f5>] sys_mmap+0x115/0x140
May 30 18:44:49 lin2 kernel: [<ffffffff8020b7fb>]
system_call_after_swapgs+0x7b/0x80
May 30 18:44:49 lin2 kernel: [<ffffffffffffffff>] 0xffffffffffffffff
May 30 18:44:49 lin2 kernel: 
May 30 18:44:49 lin2 kernel: -> #0 (&mm->mmap_sem){----}:
May 30 18:44:49 lin2 kernel: [<ffffffff8025fc94>]
print_circular_bug_header+0xe4/0xf0
May 30 18:44:49 lin2 kernel: [<ffffffff80260d08>] __lock_acquire+0xc58/0x10a0
May 30 18:44:49 lin2 kernel: [<ffffffff8050eb35>]
_spin_unlock_irqrestore+0x65/0x80
May 30 18:44:49 lin2 kernel: [<ffffffff8025f9d7>] trace_hardirqs_on+0x117/0x160
May 30 18:44:49 lin2 kernel: [<ffffffff802611a7>] lock_acquire+0x57/0x80
May 30 18:44:49 lin2 kernel: [<ffffffffa00d7d28>]
videobuf_dma_init_user+0x48/0xa0 [videobuf_dma_sg]
May 30 18:44:49 lin2 kernel: [<ffffffff8050d7d2>] down_read+0x32/0x40
May 30 18:44:49 lin2 kernel: [<ffffffffa00d7d28>]
videobuf_dma_init_user+0x48/0xa0 [videobuf_dma_sg]
May 30 18:44:49 lin2 kernel: [<ffffffffa00d8208>] __videobuf_iolock+0xe8/0x140
[videobuf_dma_sg]
May 30 18:44:49 lin2 kernel: [<ffffffffa0117534>] buffer_prepare+0x1d4/0x220
[saa7134]
May 30 18:44:49 lin2 kernel: [<ffffffff8036f806>] __spin_lock_init+0x36/0x70
May 30 18:44:49 lin2 kernel: [<ffffffffa00c91dd>] videobuf_read_one+0x30d/0x458
[videobuf_core]
May 30 18:44:49 lin2 kernel: [<ffffffff8050f116>] unlock_kernel+0x36/0x60
May 30 18:44:49 lin2 kernel: [<ffffffff802b3a58>] vfs_read+0xc8/0x170
May 30 18:44:49 lin2 kernel: [<ffffffff802b3c03>] sys_read+0x53/0xa0
May 30 18:44:49 lin2 kernel: [<ffffffff8020b7fb>]
system_call_after_swapgs+0x7b/0x80
May 30 18:44:49 lin2 kernel: [<ffffffffffffffff>] 0xffffffffffffffff
May 30 18:44:49 lin2 kernel: 
May 30 18:44:49 lin2 kernel: other info that might help us debug this:
May 30 18:44:49 lin2 kernel: 
May 30 18:44:49 lin2 kernel: 1 lock held by xawtv/3063:
May 30 18:44:49 lin2 kernel: #0:  (&q->vb_lock){--..}, at: [<ffffffffa00c8f16>]
videobuf_read_one+0x46/0x458 [videobuf_core]
May 30 18:44:49 lin2 kernel: 
May 30 18:44:49 lin2 kernel: stack backtrace:
May 30 18:44:49 lin2 kernel: Pid: 3063, comm: xawtv Not tainted
2.6.26-rc3-08493-gb8291ad-dirty #18
May 30 18:44:49 lin2 kernel: 
May 30 18:44:49 lin2 kernel: Call Trace:
May 30 18:44:49 lin2 kernel: [<ffffffff8025fde9>]
print_circular_bug_tail+0x89/0x90
May 30 18:44:49 lin2 kernel: [<ffffffff8025fc94>]
print_circular_bug_header+0xe4/0xf0
May 30 18:44:49 lin2 kernel: [<ffffffff80260d08>] __lock_acquire+0xc58/0x10a0
May 30 18:44:49 lin2 kernel: [<ffffffff8050eb35>]
_spin_unlock_irqrestore+0x65/0x80
May 30 18:44:49 lin2 kernel: [<ffffffff8025f9d7>] trace_hardirqs_on+0x117/0x160
May 30 18:44:49 lin2 kernel: [<ffffffff802611a7>] lock_acquire+0x57/0x80
May 30 18:44:49 lin2 kernel: [<ffffffffa00d7d28>]
:videobuf_dma_sg:videobuf_dma_init_user+0x48/0xa0
May 30 18:44:49 lin2 kernel: [<ffffffff8050d7d2>] down_read+0x32/0x40
May 30 18:44:49 lin2 kernel: [<ffffffffa00d7d28>]
:videobuf_dma_sg:videobuf_dma_init_user+0x48/0xa0
May 30 18:44:49 lin2 kernel: [<ffffffffa00d8208>]
:videobuf_dma_sg:__videobuf_iolock+0xe8/0x140
May 30 18:44:49 lin2 kernel: [<ffffffffa0117534>]
:saa7134:buffer_prepare+0x1d4/0x220
May 30 18:44:49 lin2 kernel: [<ffffffff8036f806>] __spin_lock_init+0x36/0x70
May 30 18:44:49 lin2 kernel: [<ffffffffa00c91dd>]
:videobuf_core:videobuf_read_one+0x30d/0x458
May 30 18:44:49 lin2 kernel: [<ffffffff8050f116>] unlock_kernel+0x36/0x60
May 30 18:44:49 lin2 kernel: [<ffffffff802b3a58>] vfs_read+0xc8/0x170
May 30 18:44:49 lin2 kernel: [<ffffffff802b3c03>] sys_read+0x53/0xa0
May 30 18:44:49 lin2 kernel: [<ffffffff8020b7fb>]
system_call_after_swapgs+0x7b/0x80


-- 
Configure bugmail: http://bugzilla.kernel.org/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
You are on the CC list for the bug, or are watching someone who is.

More information about the Bugme-new mailing list