From: Takashi Iwai <tiwai@suse.de>
Date: Fri, 13 Dec 2019 08:51:10 +0000 (+0100)
Subject: ALSA: hda/ca0132 - Avoid endless loop
X-Git-Tag: v3.16.83~120
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=e3497b5bb6b691199574803a9dfe66f2efdde1b9;p=thirdparty%2Fkernel%2Fstable.git

ALSA: hda/ca0132 - Avoid endless loop

commit cb04fc3b6b076f67d228a0b7d096c69ad486c09c upstream.

Introduce a timeout to dspio_clear_response_queue() so that it won't
be caught in an endless loop even if the hardware doesn't respond
properly.

Fixes: a73d511c4867 ("ALSA: hda/ca0132: Add unsol handler for DSP and jack detection")
Link: https://lore.kernel.org/r/20191213085111.22855-3-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---

diff --git a/sound/pci/hda/patch_ca0132.c b/sound/pci/hda/patch_ca0132.c
index 554a138efdbfe..9e2387efa4ec8 100644
--- a/sound/pci/hda/patch_ca0132.c
+++ b/sound/pci/hda/patch_ca0132.c
@@ -1271,13 +1271,14 @@ struct scp_msg {
 
 static void dspio_clear_response_queue(struct hda_codec *codec)
 {
+	unsigned long timeout = jiffies + msecs_to_jiffies(1000);
 	unsigned int dummy = 0;
-	int status = -1;
+	int status;
 
 	/* clear all from the response queue */
 	do {
 		status = dspio_read(codec, &dummy);
-	} while (status == 0);
+	} while (status == 0 && time_before(jiffies, timeout));
 }
 
 static int dspio_get_response_data(struct hda_codec *codec)