[alsa-devel] aplay: possible circular locking dependency detected

[Daniel Mack]

I got this once while testing an USB audio device. Appeareantly not reproducable.

Daniel


Feb 21 14:26:29 jup kernel: [69661.385427] 
Feb 21 14:26:29 jup kernel: [69661.385430] =======================================================
Feb 21 14:26:29 jup kernel: [69661.385435] [ INFO: possible circular locking dependency detected ]
Feb 21 14:26:29 jup kernel: [69661.385439] 2.6.33-rc8 #21
Feb 21 14:26:29 jup kernel: [69661.385441] -------------------------------------------------------
Feb 21 14:26:29 jup kernel: [69661.385444] aplay/11761 is trying to acquire lock:
Feb 21 14:26:29 jup kernel: [69661.385446]  (sysfs_mutex){+.+.+.}, at: [<c10f0668>] sysfs_get_dirent+0x15/0x4c
Feb 21 14:26:29 jup kernel: [69661.385457] 
Feb 21 14:26:29 jup kernel: [69661.385457] but task is already holding lock:
Feb 21 14:26:29 jup kernel: [69661.385460]  (&pcm->open_mutex){+.+.+.}, at: [<fb68bc8e>] snd_pcm_release+0x55/0x9e [snd_pcm]
Feb 21 14:26:29 jup kernel: [69661.385474] 
Feb 21 14:26:29 jup kernel: [69661.385474] which lock already depends on the new lock.
Feb 21 14:26:29 jup kernel: [69661.385476] 
Feb 21 14:26:29 jup kernel: [69661.385478] 
Feb 21 14:26:29 jup kernel: [69661.385479] the existing dependency chain (in reverse order) is:
Feb 21 14:26:29 jup kernel: [69661.385481] 
Feb 21 14:26:29 jup kernel: [69661.385482] -> #2 (&pcm->open_mutex){+.+.+.}:
Feb 21 14:26:29 jup kernel: [69661.385487]        [<c1059070>] __lock_acquire+0x10ff/0x1422
Feb 21 14:26:29 jup kernel: [69661.385493]        [<c105943b>] lock_acquire+0xa8/0xbf
Feb 21 14:26:29 jup kernel: [69661.385498]        [<c13720d3>] mutex_lock_nested+0x47/0x2b2
Feb 21 14:26:29 jup kernel: [69661.385503]        [<fb68bc8e>] snd_pcm_release+0x55/0x9e [snd_pcm]
Feb 21 14:26:29 jup kernel: [69661.385513]        [<c10aabe9>] __fput+0xeb/0x196
Feb 21 14:26:29 jup kernel: [69661.385517]        [<c10aacad>] fput+0x19/0x1b
Feb 21 14:26:29 jup kernel: [69661.385522]        [<c109ae3b>] remove_vma+0x39/0x58
Feb 21 14:26:29 jup kernel: [69661.385528]        [<c109bab3>] do_munmap+0x23c/0x259
Feb 21 14:26:29 jup kernel: [69661.385532]        [<c109bb00>] sys_munmap+0x30/0x3f
Feb 21 14:26:29 jup kernel: [69661.385536]        [<c10028d0>] sysenter_do_call+0x12/0x36
Feb 21 14:26:29 jup kernel: [69661.385541] 
Feb 21 14:26:29 jup kernel: [69661.385542] -> #1 (&mm->mmap_sem){++++++}:
Feb 21 14:26:29 jup kernel: [69661.385547]        [<c1059070>] __lock_acquire+0x10ff/0x1422
Feb 21 14:26:29 jup kernel: [69661.385551]        [<c105943b>] lock_acquire+0xa8/0xbf
Feb 21 14:26:29 jup kernel: [69661.385556]        [<c10968db>] might_fault+0x6b/0x88
Feb 21 14:26:29 jup kernel: [69661.385561]        [<c11b3cf0>] copy_to_user+0x2c/0xfc
Feb 21 14:26:29 jup kernel: [69661.385565]        [<c10b5e73>] filldir64+0x97/0xcd
Feb 21 14:26:29 jup kernel: [69661.385570]        [<c10f0534>] sysfs_readdir+0x117/0x14b
Feb 21 14:26:29 jup kernel: [69661.385574]        [<c10b6085>] vfs_readdir+0x68/0x94
Feb 21 14:26:29 jup kernel: [69661.385578]        [<c10b6114>] sys_getdents64+0x63/0xa0
Feb 21 14:26:29 jup kernel: [69661.385582]        [<c10028d0>] sysenter_do_call+0x12/0x36
Feb 21 14:26:29 jup kernel: [69661.385587] 
Feb 21 14:26:29 jup kernel: [69661.385587] -> #0 (sysfs_mutex){+.+.+.}:
Feb 21 14:26:29 jup kernel: [69661.385592]        [<c1058dc6>] __lock_acquire+0xe55/0x1422
Feb 21 14:26:29 jup kernel: [69661.385597]        [<c105943b>] lock_acquire+0xa8/0xbf
Feb 21 14:26:29 jup kernel: [69661.385601]        [<c13720d3>] mutex_lock_nested+0x47/0x2b2
Feb 21 14:26:29 jup kernel: [69661.385605]        [<c10f0668>] sysfs_get_dirent+0x15/0x4c
Feb 21 14:26:29 jup kernel: [69661.385609]        [<c10f1b4a>] sysfs_remove_group+0x1e/0xa3
Feb 21 14:26:29 jup kernel: [69661.385614]        [<c12359b8>] dpm_sysfs_remove+0x10/0x12
Feb 21 14:26:29 jup kernel: [69661.385619]        [<c123114c>] device_del+0x33/0x154
Feb 21 14:26:29 jup kernel: [69661.385625]        [<c1231278>] device_unregister+0xb/0x15
Feb 21 14:26:29 jup kernel: [69661.385629]        [<c129a209>] usb_remove_ep_devs+0x15/0x1f
Feb 21 14:26:29 jup kernel: [69661.385635]        [<c12943ff>] remove_intf_ep_devs+0x21/0x32
Feb 21 14:26:29 jup kernel: [69661.385640]        [<c12954ea>] usb_set_interface+0x18c/0x22c
Feb 21 14:26:29 jup kernel: [69661.385644]        [<fc703cd7>] snd_usb_playback_close+0x20/0x33 [snd_usb_audio]
Feb 21 14:26:29 jup kernel: [69661.385654]        [<fb68bc10>] snd_pcm_release_substream+0x3d/0x66 [snd_pcm]
Feb 21 14:26:29 jup kernel: [69661.385664]        [<fb68bc95>] snd_pcm_release+0x5c/0x9e [snd_pcm]
Feb 21 14:26:29 jup kernel: [69661.385673]        [<c10aabe9>] __fput+0xeb/0x196
Feb 21 14:26:29 jup kernel: [69661.385677]        [<c10aacad>] fput+0x19/0x1b
Feb 21 14:26:29 jup kernel: [69661.385681]        [<c109ae3b>] remove_vma+0x39/0x58
Feb 21 14:26:29 jup kernel: [69661.385685]        [<c109bab3>] do_munmap+0x23c/0x259
Feb 21 14:26:29 jup kernel: [69661.385689]        [<c109bb00>] sys_munmap+0x30/0x3f
Feb 21 14:26:29 jup kernel: [69661.385693]        [<c10028d0>] sysenter_do_call+0x12/0x36
Feb 21 14:26:29 jup kernel: [69661.385698] 
Feb 21 14:26:29 jup kernel: [69661.385698] other info that might help us debug this:
Feb 21 14:26:29 jup kernel: [69661.385700] 
Feb 21 14:26:29 jup kernel: [69661.385702] 2 locks held by aplay/11761:
Feb 21 14:26:29 jup kernel: [69661.385705]  #0:  (&mm->mmap_sem){++++++}, at: [<c109baf3>] sys_munmap+0x23/0x3f
Feb 21 14:26:29 jup kernel: [69661.385711]  #1:  (&pcm->open_mutex){+.+.+.}, at: [<fb68bc8e>] snd_pcm_release+0x55/0x9e [snd_pcm]
Feb 21 14:26:29 jup kernel: [69661.385723] 
Feb 21 14:26:29 jup kernel: [69661.385724] stack backtrace:
Feb 21 14:26:29 jup kernel: [69661.385727] Pid: 11761, comm: aplay Not tainted 2.6.33-rc8 #21
Feb 21 14:26:29 jup kernel: [69661.385730] Call Trace:
Feb 21 14:26:29 jup kernel: [69661.385735]  [<c137062c>] ? printk+0xf/0x11
Feb 21 14:26:29 jup kernel: [69661.385740]  [<c1057b26>] print_circular_bug+0x90/0x9c
Feb 21 14:26:29 jup kernel: [69661.385744]  [<c1058dc6>] __lock_acquire+0xe55/0x1422
Feb 21 14:26:29 jup kernel: [69661.385748]  [<c105917f>] ? __lock_acquire+0x120e/0x1422
Feb 21 14:26:29 jup kernel: [69661.385753]  [<c103d4d3>] ? try_to_del_timer_sync+0x9c/0xa4
Feb 21 14:26:29 jup kernel: [69661.385758]  [<c105943b>] lock_acquire+0xa8/0xbf
Feb 21 14:26:29 jup kernel: [69661.385762]  [<c10f0668>] ? sysfs_get_dirent+0x15/0x4c
Feb 21 14:26:29 jup kernel: [69661.385766]  [<c10f0668>] ? sysfs_get_dirent+0x15/0x4c
Feb 21 14:26:29 jup kernel: [69661.385769]  [<c13720d3>] mutex_lock_nested+0x47/0x2b2
Feb 21 14:26:29 jup kernel: [69661.385773]  [<c10f0668>] ? sysfs_get_dirent+0x15/0x4c
Feb 21 14:26:29 jup kernel: [69661.385777]  [<c137187f>] ? __mutex_unlock_slowpath+0xe9/0x105
Feb 21 14:26:29 jup kernel: [69661.385781]  [<c10572e5>] ? trace_hardirqs_on_caller+0xff/0x120
Feb 21 14:26:29 jup kernel: [69661.385785]  [<c10f0668>] sysfs_get_dirent+0x15/0x4c
Feb 21 14:26:29 jup kernel: [69661.385789]  [<c10f1b4a>] sysfs_remove_group+0x1e/0xa3
Feb 21 14:26:29 jup kernel: [69661.385793]  [<c12359b8>] dpm_sysfs_remove+0x10/0x12
Feb 21 14:26:29 jup kernel: [69661.385797]  [<c123114c>] device_del+0x33/0x154
Feb 21 14:26:29 jup kernel: [69661.385801]  [<c1231278>] device_unregister+0xb/0x15
Feb 21 14:26:29 jup kernel: [69661.385805]  [<c129a209>] usb_remove_ep_devs+0x15/0x1f
Feb 21 14:26:29 jup kernel: [69661.385809]  [<c12943ff>] remove_intf_ep_devs+0x21/0x32
Feb 21 14:26:29 jup kernel: [69661.385813]  [<c12954ea>] usb_set_interface+0x18c/0x22c
Feb 21 14:26:29 jup kernel: [69661.385822]  [<fc703cd7>] snd_usb_playback_close+0x20/0x33 [snd_usb_audio]
Feb 21 14:26:29 jup kernel: [69661.385830]  [<fb68bc10>] snd_pcm_release_substream+0x3d/0x66 [snd_pcm]
Feb 21 14:26:29 jup kernel: [69661.385839]  [<fb68bc95>] snd_pcm_release+0x5c/0x9e [snd_pcm]
Feb 21 14:26:29 jup kernel: [69661.385843]  [<c10aabe9>] __fput+0xeb/0x196
Feb 21 14:26:29 jup kernel: [69661.385847]  [<c10aacad>] fput+0x19/0x1b
Feb 21 14:26:29 jup kernel: [69661.385851]  [<c109ae3b>] remove_vma+0x39/0x58
Feb 21 14:26:29 jup kernel: [69661.385854]  [<c109bab3>] do_munmap+0x23c/0x259
Feb 21 14:26:29 jup kernel: [69661.385858]  [<c109bb00>] sys_munmap+0x30/0x3f
Feb 21 14:26:29 jup kernel: [69661.385862]  [<c10028d0>] sysenter_do_call+0x12/0x36