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mirror of https://github.com/edk2-porting/linux-next.git synced 2024-12-24 05:04:00 +08:00
linux-next/sound/usb/line6
Andrej Krutak adc8a43a6d ALSA: line6: Give up on the lock while URBs are released.
Done, because line6_stream_stop() locks and calls line6_unlink_audio_urbs(),
which in turn invokes audio_out_callback(), which tries to lock 2nd time.

Fixes:

=============================================
[ INFO: possible recursive locking detected ]
4.4.15+ #15 Not tainted
---------------------------------------------
mplayer/3591 is trying to acquire lock:
 (&(&line6pcm->out.lock)->rlock){-.-...}, at: [<bfa27655>] audio_out_callback+0x70/0x110 [snd_usb_line6]

but task is already holding lock:
 (&(&line6pcm->out.lock)->rlock){-.-...}, at: [<bfa26aad>] line6_stream_stop+0x24/0x5c [snd_usb_line6]

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(&(&line6pcm->out.lock)->rlock);
  lock(&(&line6pcm->out.lock)->rlock);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

3 locks held by mplayer/3591:
 #0:  (snd_pcm_link_rwlock){.-.-..}, at: [<bf8d49a7>] snd_pcm_stream_lock+0x1e/0x40 [snd_pcm]
 #1:  (&(&substream->self_group.lock)->rlock){-.-...}, at: [<bf8d49af>] snd_pcm_stream_lock+0x26/0x40 [snd_pcm]
 #2:  (&(&line6pcm->out.lock)->rlock){-.-...}, at: [<bfa26aad>] line6_stream_stop+0x24/0x5c [snd_usb_line6]

stack backtrace:
CPU: 0 PID: 3591 Comm: mplayer Not tainted 4.4.15+ #15
Hardware name: Generic AM33XX (Flattened Device Tree)
[<c0015d85>] (unwind_backtrace) from [<c001253d>] (show_stack+0x11/0x14)
[<c001253d>] (show_stack) from [<c02f1bdf>] (dump_stack+0x8b/0xac)
[<c02f1bdf>] (dump_stack) from [<c0076f43>] (__lock_acquire+0xc8b/0x1780)
[<c0076f43>] (__lock_acquire) from [<c007810d>] (lock_acquire+0x99/0x1c0)
[<c007810d>] (lock_acquire) from [<c06171e7>] (_raw_spin_lock_irqsave+0x3f/0x4c)
[<c06171e7>] (_raw_spin_lock_irqsave) from [<bfa27655>] (audio_out_callback+0x70/0x110 [snd_usb_line6])
[<bfa27655>] (audio_out_callback [snd_usb_line6]) from [<c04294db>] (__usb_hcd_giveback_urb+0x53/0xd0)
[<c04294db>] (__usb_hcd_giveback_urb) from [<c046388d>] (musb_giveback+0x3d/0x98)
[<c046388d>] (musb_giveback) from [<c04647f5>] (musb_urb_dequeue+0x6d/0x114)
[<c04647f5>] (musb_urb_dequeue) from [<c042ac11>] (usb_hcd_unlink_urb+0x39/0x98)
[<c042ac11>] (usb_hcd_unlink_urb) from [<bfa26a87>] (line6_unlink_audio_urbs+0x6a/0x6c [snd_usb_line6])
[<bfa26a87>] (line6_unlink_audio_urbs [snd_usb_line6]) from [<bfa26acb>] (line6_stream_stop+0x42/0x5c [snd_usb_line6])
[<bfa26acb>] (line6_stream_stop [snd_usb_line6]) from [<bfa26fe7>] (snd_line6_trigger+0xb6/0xf4 [snd_usb_line6])
[<bfa26fe7>] (snd_line6_trigger [snd_usb_line6]) from [<bf8d47b7>] (snd_pcm_do_stop+0x36/0x38 [snd_pcm])
[<bf8d47b7>] (snd_pcm_do_stop [snd_pcm]) from [<bf8d462f>] (snd_pcm_action_single+0x22/0x40 [snd_pcm])
[<bf8d462f>] (snd_pcm_action_single [snd_pcm]) from [<bf8d46f9>] (snd_pcm_action+0xac/0xb0 [snd_pcm])
[<bf8d46f9>] (snd_pcm_action [snd_pcm]) from [<bf8d4b61>] (snd_pcm_drop+0x38/0x64 [snd_pcm])
[<bf8d4b61>] (snd_pcm_drop [snd_pcm]) from [<bf8d6233>] (snd_pcm_common_ioctl1+0x7fe/0xbe8 [snd_pcm])
[<bf8d6233>] (snd_pcm_common_ioctl1 [snd_pcm]) from [<bf8d6779>] (snd_pcm_playback_ioctl1+0x15c/0x51c [snd_pcm])
[<bf8d6779>] (snd_pcm_playback_ioctl1 [snd_pcm]) from [<bf8d6b59>] (snd_pcm_playback_ioctl+0x20/0x28 [snd_pcm])
[<bf8d6b59>] (snd_pcm_playback_ioctl [snd_pcm]) from [<c016714b>] (do_vfs_ioctl+0x3af/0x5c8)

Fixes: 63e20df1e5 ('ALSA: line6: Reorganize PCM stream handling')
Cc: <stable@vger.kernel.org> # v4.0+
Reviewed-by: Stefan Hajnoczi <stefanha@gmail.com>
Signed-off-by: Andrej Krutak <dev@andree.sk>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2016-08-22 11:37:16 +02:00
..
capture.c ALSA: line6: Remove snd_line6_ prefix of pcm property fields 2015-01-28 20:54:47 +01:00
capture.h ALSA: line6: Reorganize PCM stream handling 2015-01-28 07:22:36 +01:00
driver.c ALSA: line6: Improve line6_read/write_data() interfaces 2015-02-12 11:07:48 +01:00
driver.h ALSA: line6: Improve line6_read/write_data() interfaces 2015-02-12 11:07:48 +01:00
Kconfig ALSA: line6/toneport: Implement LED controls via LED class 2015-01-28 07:20:08 +01:00
Makefile ALSA: line6: Reorganize card resource handling 2015-01-20 08:17:16 +01:00
midi.c ALSA: line6: Move the contents of usbdefs.h into driver.h 2015-01-28 20:54:45 +01:00
midi.h ALSA: line6: Tidy up and typo fixes in comments 2015-01-28 20:54:43 +01:00
midibuf.c ALSA: line6: Remove unused line6_midibuf_skip_message() 2015-02-01 09:35:25 +01:00
midibuf.h ALSA: line6: Remove unused line6_midibuf_skip_message() 2015-02-01 09:35:25 +01:00
pcm.c ALSA: line6: Give up on the lock while URBs are released. 2016-08-22 11:37:16 +02:00
pcm.h ALSA: line6: Remove snd_line6_ prefix of pcm property fields 2015-01-28 20:54:47 +01:00
playback.c ALSA: line6: Clamp values correctly 2015-03-05 13:03:28 +01:00
playback.h ALSA: line6: Reorganize PCM stream handling 2015-01-28 07:22:36 +01:00
pod.c ALSA: line6: Use explicit type for serial number 2015-02-11 10:39:05 +01:00
podhd.c ALSA: line6: Pass driver name to line6_probe() 2015-02-08 09:07:07 +01:00
toneport.c ALSA: line6: toneport: Use explicit type for firmware version 2015-02-11 10:41:59 +01:00
variax.c ALSA: line6: Pass driver name to line6_probe() 2015-02-08 09:07:07 +01:00