ALSA: Avoid endless sleep after disconnect

When disconnect callback is called, each component should wake up
sleepers and check card->shutdown flag for avoiding the endless sleep
blocking the proper resource release.

Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

1 files changed, 20 insertions, 0 deletions

diff --git a/sound/core/rawmidi.c b/sound/core/rawmidi.c
index 7d4f62ab6711..1bb95aeea084 100644
--- a/sound/core/rawmidi.c
+++ b/sound/core/rawmidi.c
@@ -424,6 +424,10 @@ static int snd_rawmidi_open(struct inode *inode, struct file *file)
 		mutex_unlock(&rmidi->open_mutex);
 		schedule();
 		mutex_lock(&rmidi->open_mutex);
+		if (rmidi->card->shutdown) {
+			err = -ENODEV;
+			break;
+		}
 		if (signal_pending(current)) {
 			err = -ERESTARTSYS;
 			break;
@@ -995,6 +999,8 @@ static ssize_t snd_rawmidi_read(struct file *file, char __user *buf, size_t coun
 			spin_unlock_irq(&runtime->lock);
 			schedule();
 			remove_wait_queue(&runtime->sleep, &wait);
+			if (rfile->rmidi->card->shutdown)
+				return -ENODEV;
 			if (signal_pending(current))
 				return result > 0 ? result : -ERESTARTSYS;
 			if (!runtime->avail)
@@ -1238,6 +1244,8 @@ static ssize_t snd_rawmidi_write(struct file *file, const char __user *buf,
 			spin_unlock_irq(&runtime->lock);
 			timeout = schedule_timeout(30 * HZ);
 			remove_wait_queue(&runtime->sleep, &wait);
+			if (rfile->rmidi->card->shutdown)
+				return -ENODEV;
 			if (signal_pending(current))
 				return result > 0 ? result : -ERESTARTSYS;
 			if (!runtime->avail && !timeout)
@@ -1613,9 +1621,20 @@ static int snd_rawmidi_dev_register(struct snd_device *device)
 static int snd_rawmidi_dev_disconnect(struct snd_device *device)
 {
 	struct snd_rawmidi *rmidi = device->device_data;
+	int dir;
 
 	mutex_lock(&register_mutex);
+	mutex_lock(&rmidi->open_mutex);
+	wake_up(&rmidi->open_wait);
 	list_del_init(&rmidi->list);
+	for (dir = 0; dir < 2; dir++) {
+		struct snd_rawmidi_substream *s;
+		list_for_each_entry(s, &rmidi->streams[dir].substreams, list) {
+			if (s->runtime)
+				wake_up(&s->runtime->sleep);
+		}
+	}
+
 #ifdef CONFIG_SND_OSSEMUL
 	if (rmidi->ossreg) {
 		if ((int)rmidi->device == midi_map[rmidi->card->number]) {
@@ -1630,6 +1649,7 @@ static int snd_rawmidi_dev_disconnect(struct snd_device *device)
 	}
 #endif /* CONFIG_SND_OSSEMUL */
 	snd_unregister_device(SNDRV_DEVICE_TYPE_RAWMIDI, rmidi->card, rmidi->device);
+	mutex_unlock(&rmidi->open_mutex);
 	mutex_unlock(&register_mutex);
 	return 0;
 }