[ 3.5.y.z extended stable ] Patch "ALSA: ua101: Fix unlocked snd_pcm_stop() call" has been added to staging queue

[Luis Henriques]

This is a note to let you know that I have just added a patch titled

    ALSA: ua101: Fix unlocked snd_pcm_stop() call

to the linux-3.5.y-queue branch of the 3.5.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.5.y-queue

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.5.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

>From 0b2b0ad9ebbf50a98271f0d5e6afc456792b0d49 Mon Sep 17 00:00:00 2001
From: Takashi Iwai <tiwai at suse.de>
Date: Thu, 11 Jul 2013 17:58:25 +0200
Subject: [PATCH] ALSA: ua101: Fix unlocked snd_pcm_stop() call

commit 9538aa46c2427d6782aa10036c4da4c541605e0e upstream.

snd_pcm_stop() must be called in the PCM substream lock context.

Acked-by: Clemens Ladisch <clemens at ladisch.de>
Signed-off-by: Takashi Iwai <tiwai at suse.de>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 sound/usb/misc/ua101.c | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/sound/usb/misc/ua101.c b/sound/usb/misc/ua101.c
index 8b81cb5..d97d35d 100644
--- a/sound/usb/misc/ua101.c
+++ b/sound/usb/misc/ua101.c
@@ -613,14 +613,24 @@ static int start_usb_playback(struct ua101 *ua)

 static void abort_alsa_capture(struct ua101 *ua)
 {
-	if (test_bit(ALSA_CAPTURE_RUNNING, &ua->states))
+	unsigned long flags;
+
+	if (test_bit(ALSA_CAPTURE_RUNNING, &ua->states)) {
+		snd_pcm_stream_lock_irqsave(ua->capture.substream, flags);
 		snd_pcm_stop(ua->capture.substream, SNDRV_PCM_STATE_XRUN);
+		snd_pcm_stream_unlock_irqrestore(ua->capture.substream, flags);
+	}
 }

 static void abort_alsa_playback(struct ua101 *ua)
 {
-	if (test_bit(ALSA_PLAYBACK_RUNNING, &ua->states))
+	unsigned long flags;
+
+	if (test_bit(ALSA_PLAYBACK_RUNNING, &ua->states)) {
+		snd_pcm_stream_lock_irqsave(ua->playback.substream, flags);
 		snd_pcm_stop(ua->playback.substream, SNDRV_PCM_STATE_XRUN);
+		snd_pcm_stream_unlock_irqrestore(ua->playback.substream, flags);
+	}
 }

 static int set_stream_hw(struct ua101 *ua, struct snd_pcm_substream *substream,
--
1.8.1.2