[ALSA] Fix possible races in timer callbacks

Fix possible races in timer callbacks.

Signed-off-by: Takashi Iwai <tiwai@suse.de>

1 files changed, 3 insertions, 2 deletions

diff --git a/sound/drivers/opl3/opl3_midi.c b/sound/drivers/opl3/opl3_midi.c
index 48c480e050ce..1b6f227af370 100644
--- a/sound/drivers/opl3/opl3_midi.c
+++ b/sound/drivers/opl3/opl3_midi.c
@@ -238,10 +238,11 @@ void snd_opl3_timer_func(unsigned long data)
 {
 
         struct snd_opl3 *opl3 = (struct snd_opl3 *)data;
+        unsigned long flags;
         int again = 0;
         int i;
 
-        spin_lock(&opl3->sys_timer_lock);
+        spin_lock_irqsave(&opl3->sys_timer_lock, flags);
         for (i = 0; i < opl3->max_voices; i++) {
                 struct snd_opl3_voice *vp = &opl3->voices[i];
                 if (vp->state > 0 && vp->note_off_check) {
@@ -257,7 +258,7 @@ void snd_opl3_timer_func(unsigned long data)
         } else {
                 opl3->sys_timer_status = 0;
         }
-        spin_unlock(&opl3->sys_timer_lock);
+        spin_unlock_irqrestore(&opl3->sys_timer_lock, flags);
 }
 
 /*