From: Dr. David Alan Gilbert <dgilbert@redhat.com>
Date: Tue, 24 Jul 2018 10:22:15 +0000 (+0100)
Subject: audio/hda: Fix migration
X-Git-Tag: qemu-xen-4.12.0-rc1~26^2~4
X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=67fa1f5700248fc66d5b1526c268737e29892b86;p=qemu-xen.git

audio/hda: Fix migration

Fix outgoing migration which was crashing in
vmstate_hda_audio_stream_buf_needed, I think the problem
is that we have room for upto 4 streams in the array but only
use 2, when we come to try and save the state of the unused
streams we hit st->state == NULL.

Fixes: 280c1e1cdb24d80ecdfc
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20180724102215.31866-1-dgilbert@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
---

diff --git a/hw/audio/hda-codec.c b/hw/audio/hda-codec.c
index 2b58c3505b..617a1c1016 100644
--- a/hw/audio/hda-codec.c
+++ b/hw/audio/hda-codec.c
@@ -786,7 +786,7 @@ static void hda_audio_reset(DeviceState *dev)
 static bool vmstate_hda_audio_stream_buf_needed(void *opaque)
 {
     HDAAudioStream *st = opaque;
-    return st->state->use_timer;
+    return st->state && st->state->use_timer;
 }
 
 static const VMStateDescription vmstate_hda_audio_stream_buf = {