From: Takashi Iwai <tiwai@suse.de>
Date: Thu, 13 Jul 2006 18:08:01 +0000 (+0200)
Subject: ALSA: Fix a deadlock in snd-rtctimer
X-Git-Tag: v2.6.17.7~16
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=62d99ac2aeb0a91d7f5f3a4f1532c686b736b37e;p=thirdparty%2Fkernel%2Fstable.git

ALSA: Fix a deadlock in snd-rtctimer

Fix an occasional deadlock occuring with snd-rtctimer driver,
added irqsave to the lock in tasklet (ALSA bug#952).

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---

diff --git a/sound/core/timer.c b/sound/core/timer.c
index cdeeb639b675a..4585600ba0be6 100644
--- a/sound/core/timer.c
+++ b/sound/core/timer.c
@@ -628,8 +628,9 @@ static void snd_timer_tasklet(unsigned long arg)
 	struct snd_timer_instance *ti;
 	struct list_head *p;
 	unsigned long resolution, ticks;
+	unsigned long flags;
 
-	spin_lock(&timer->lock);
+	spin_lock_irqsave(&timer->lock, flags);
 	/* now process all callbacks */
 	while (!list_empty(&timer->sack_list_head)) {
 		p = timer->sack_list_head.next;		/* get first item */
@@ -649,7 +650,7 @@ static void snd_timer_tasklet(unsigned long arg)
 		spin_lock(&timer->lock);
 		ti->flags &= ~SNDRV_TIMER_IFLG_CALLBACK;
 	}
-	spin_unlock(&timer->lock);
+	spin_unlock_irqrestore(&timer->lock, flags);
 }
 
 /*