linux/sound
Takashi Iwai 0725dda207 ALSA: usb-audio: Fix device_del() sysfs warnings at disconnect
Some USB-audio devices show weird sysfs warnings at disconnecting the
devices, e.g.
 usb 1-3: USB disconnect, device number 3
 ------------[ cut here ]------------
 WARNING: CPU: 0 PID: 973 at fs/sysfs/group.c:216 device_del+0x39/0x180()
 sysfs group ffffffff8183df40 not found for kobject 'midiC1D0'
 Call Trace:
  [<ffffffff814a3e38>] ? dump_stack+0x49/0x71
  [<ffffffff8103cb72>] ? warn_slowpath_common+0x82/0xb0
  [<ffffffff8103cc55>] ? warn_slowpath_fmt+0x45/0x50
  [<ffffffff813521e9>] ? device_del+0x39/0x180
  [<ffffffff81352339>] ? device_unregister+0x9/0x20
  [<ffffffff81352384>] ? device_destroy+0x34/0x40
  [<ffffffffa00ba29f>] ? snd_unregister_device+0x7f/0xd0 [snd]
  [<ffffffffa025124e>] ? snd_rawmidi_dev_disconnect+0xce/0x100 [snd_rawmidi]
  [<ffffffffa00c0192>] ? snd_device_disconnect+0x62/0x90 [snd]
  [<ffffffffa00c025c>] ? snd_device_disconnect_all+0x3c/0x60 [snd]
  [<ffffffffa00bb574>] ? snd_card_disconnect+0x124/0x1a0 [snd]
  [<ffffffffa02e54e8>] ? usb_audio_disconnect+0x88/0x1c0 [snd_usb_audio]
  [<ffffffffa015260e>] ? usb_unbind_interface+0x5e/0x1b0 [usbcore]
  [<ffffffff813553e9>] ? __device_release_driver+0x79/0xf0
  [<ffffffff81355485>] ? device_release_driver+0x25/0x40
  [<ffffffff81354e11>] ? bus_remove_device+0xf1/0x130
  [<ffffffff813522b9>] ? device_del+0x109/0x180
  [<ffffffffa01501d5>] ? usb_disable_device+0x95/0x1f0 [usbcore]
  [<ffffffffa014634f>] ? usb_disconnect+0x8f/0x190 [usbcore]
  [<ffffffffa0149179>] ? hub_thread+0x539/0x13a0 [usbcore]
  [<ffffffff810669f5>] ? sched_clock_local+0x15/0x80
  [<ffffffff81066c98>] ? sched_clock_cpu+0xb8/0xd0
  [<ffffffff81070730>] ? bit_waitqueue+0xb0/0xb0
  [<ffffffffa0148c40>] ? usb_port_resume+0x430/0x430 [usbcore]
  [<ffffffffa0148c40>] ? usb_port_resume+0x430/0x430 [usbcore]
  [<ffffffff8105973e>] ? kthread+0xce/0xf0
  [<ffffffff81059670>] ? kthread_create_on_node+0x1c0/0x1c0
  [<ffffffff814a8b7c>] ? ret_from_fork+0x7c/0xb0
  [<ffffffff81059670>] ? kthread_create_on_node+0x1c0/0x1c0
 ---[ end trace 40b1928d1136b91e ]---

This comes from the fact that usb-audio driver may receive the
disconnect callback multiple times, per each usb interface.  When a
device has both audio and midi interfaces, it gets called twice, and
currently the driver tries to release resources at the last call.
At this point, the first parent interface has been already deleted,
thus deleting a child of the first parent hits such a warning.

For fixing this problem, we need to call snd_card_disconnect() and
cancel pending operations at the very first disconnect while the
release of the whole objects waits until the last disconnect call.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=80931
Reported-and-tested-by: Tomas Gayoso <tgayoso@gmail.com>
Reported-and-tested-by: Chris J Arges <chris.j.arges@canonical.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2014-11-05 15:36:25 +01:00
..
aoa ALSA: Use dma_zalloc_coherent 2014-06-16 11:39:45 +02:00
arm ASoC: pxa2xx-ac97: prepare and unprepare the clocks 2014-06-09 21:11:18 +01:00
atmel dmaengine: dw: split dma-dw.h to platform and private parts 2014-10-15 20:31:04 +05:30
core ALSA: pcm: Zero-clear reserved fields of PCM status ioctl in compat mode 2014-10-28 12:45:53 +01:00
drivers ALSA: vx: Use nonatomic PCM ops 2014-09-15 15:52:03 +02:00
firewire ALSA: bebob: Uninitialized id returned by saffirepro_both_clk_src_get 2014-10-27 14:09:14 +01:00
i2c
isa ALSA: gus: remove checks for CONFIG_SND_DEBUG_ROM 2014-05-30 10:12:10 +02:00
mips ALSA: au1x00: Use resource_size instead of computation 2014-05-28 17:50:57 +02:00
oss sound fixes for 3.17-rc1 2014-08-15 18:06:56 -06:00
parisc
pci ALSA: hda - fix mute led problem for three HP laptops 2014-11-05 07:42:15 +01:00
pcmcia ALSA: pdaudiocf: Use nonatomic PCM ops 2014-09-15 15:52:38 +02:00
ppc of: Migrate of_find_node_by_name() users to for_each_node_by_name() 2014-06-26 17:12:24 +01:00
sh
soc Merge remote-tracking branches 'asoc/fix/adau1761', 'asoc/fix/fsl', 'asoc/fix/intel', 'asoc/fix/s6000' and 'asoc/fix/sgtl5000' into asoc-linus 2014-10-27 11:17:41 +00:00
sparc ALSA: Use dma_zalloc_coherent 2014-06-16 11:39:45 +02:00
spi
synth ALSA: synth: emux: soundfont.c: Cleaning up memory leak 2014-06-01 14:33:09 +02:00
usb ALSA: usb-audio: Fix device_del() sysfs warnings at disconnect 2014-11-05 15:36:25 +01:00
ac97_bus.c
Kconfig
last.c
Makefile
sound_core.c
sound_firmware.c