Patch "ALSA: ali5451: Fix out-of-bound position reporting" has been added to the 4.4-stable tree

Patch "ALSA: ali5451: Fix out-of-bound position reporting" has been added to the 4.4-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    ALSA: ali5451: Fix out-of-bound position reporting

to the 4.4-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     alsa-ali5451-fix-out-of-bound-position-reporting.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From db68577966abc1aeae4ec597b3dcfa0d56e92041 Mon Sep 17 00:00:00 2001
From: Takashi Iwai <tiwai@suse.de>
Date: Wed, 21 Sep 2016 14:38:02 +0200
Subject: ALSA: ali5451: Fix out-of-bound position reporting

From: Takashi Iwai <tiwai@suse.de>

commit db68577966abc1aeae4ec597b3dcfa0d56e92041 upstream.

The pointer callbacks of ali5451 driver may return the value at the
boundary occasionally, and it results in the kernel warning like
  snd_ali5451 0000:00:06.0: BUG: , pos = 16384, buffer size = 16384, period size = 1024

It seems that folding the position offset is enough for fixing the
warning and no ill-effect has been seen by that.

Reported-by: Enrico Mioso <mrkiko.rs@gmail.com>
Tested-by: Enrico Mioso <mrkiko.rs@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 sound/pci/ali5451/ali5451.c |    2 ++
 1 file changed, 2 insertions(+)

--- a/sound/pci/ali5451/ali5451.c
+++ b/sound/pci/ali5451/ali5451.c
@@ -1408,6 +1408,7 @@ snd_ali_playback_pointer(struct snd_pcm_
 	spin_unlock(&codec->reg_lock);
 	dev_dbg(codec->card->dev, "playback pointer returned cso=%xh.\n", cso);
 
+	cso %= runtime->buffer_size;
 	return cso;
 }
 
@@ -1428,6 +1429,7 @@ static snd_pcm_uframes_t snd_ali_pointer
 	cso = inw(ALI_REG(codec, ALI_CSO_ALPHA_FMS + 2));
 	spin_unlock(&codec->reg_lock);
 
+	cso %= runtime->buffer_size;
 	return cso;
 }
 


Patches currently in stable-queue which might be from tiwai@suse.de are

queue-4.4/alsa-ali5451-fix-out-of-bound-position-reporting.patch
queue-4.4/alsa-usb-audio-extend-dragonfly-db-scale-quirk-to-cover-other-variants.patch
queue-4.4/alsa-usb-line6-use-the-same-declaration-as-definition-in-header-for-midi-manufacturer-id.patch