The recent change in sysfs triggered a kernel WARNING at unloading a sound driver like

WARNING: CPU: 3 PID: 2247 at fs/sysfs/group.c:214 sysfs_remove_group+0xe8/0xf0() sysfs group ffffffff81ab7b20 not found for kobject 'event14'

for each jack instance. It's because the unregistration of jack input device is done in dev_free callback, which is called after snd_card_disconnect(). Since device_unregister(card->card_dev) is called in snd_card_disconnect(), the whole sysfs entries belonging to card->card_dev have been already removed recursively. Thus this results in a warning as input_unregister_device() yet tries to unregister the already removed sysfs entry.

For fixing this mess, we need to unregister the jack input device at dev_disconnect callback so that it's called before unregistering the card->card_dev.

Signed-off-by: Takashi Iwai tiwai@suse.de --- sound/core/jack.c | 19 ++++++++++++++++--- 1 file changed, 16 insertions(+), 3 deletions(-)

diff --git a/sound/core/jack.c b/sound/core/jack.c index b35fe7345c20..8658578eb584 100644 --- a/sound/core/jack.c +++ b/sound/core/jack.c @@ -34,12 +34,12 @@ static int jack_switch_types[SND_JACK_SWITCH_TYPES] = { SW_LINEIN_INSERT, };

-static int snd_jack_dev_free(struct snd_device *device) +static int snd_jack_dev_disconnect(struct snd_device *device) { struct snd_jack *jack = device->device_data;

- if (jack->private_free) - jack->private_free(jack); + if (!jack->input_dev) + return 0;

/* If the input device is registered with the input subsystem * then we need to use a different deallocator. */ @@ -47,6 +47,18 @@ static int snd_jack_dev_free(struct snd_device *device) input_unregister_device(jack->input_dev); else input_free_device(jack->input_dev); + jack->input_dev = NULL; + return 0; +} + +static int snd_jack_dev_free(struct snd_device *device) +{ + struct snd_jack *jack = device->device_data; + + if (jack->private_free) + jack->private_free(jack); + + snd_jack_dev_disconnect(device);

kfree(jack->id); kfree(jack); @@ -110,6 +122,7 @@ int snd_jack_new(struct snd_card *card, const char *id, int type, static struct snd_device_ops ops = { .dev_free = snd_jack_dev_free, .dev_register = snd_jack_dev_register, + .dev_disconnect = snd_jack_dev_disconnect, };

jack = kzalloc(sizeof(struct snd_jack), GFP_KERNEL);