[PATCH v1] ALSA: virtio: reset device before deleting virtqueues

[Yuho Choi <oss.patchbox@gmail.com>]

virtsnd_remove() and virtsnd_freeze() delete the virtqueues before
resetting the device. del_vqs() frees the vring backing, but does not
provide a generic device quiesce operation. In particular, modern
virtio-pci keeps enabled queues active until the device is reset.

Reset the device before deleting the virtqueues so it can no longer
access the vring memory when that memory is released. This also covers
probe failures after DRIVER_OK, which unwind through virtsnd_remove().

Fixes: de3a9980d8c3 ("ALSA: virtio: add virtio sound driver")
Fixes: 575483e90a32 ("ALSA: virtio: introduce device suspend/resume support")
Cc: stable@vger.kernel.org
Signed-off-by: Yuho Choi <oss.patchbox@gmail.com>
---
 sound/virtio/virtio_card.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/sound/virtio/virtio_card.c b/sound/virtio/virtio_card.c
index 647190f4d5afc..6f35276416fed 100644
--- a/sound/virtio/virtio_card.c
+++ b/sound/virtio/virtio_card.c
@@ -354,8 +354,8 @@ static void virtsnd_remove(struct virtio_device *vdev)
 	if (snd->card)
 		snd_card_free(snd->card);
 
-	vdev->config->del_vqs(vdev);
 	virtio_reset_device(vdev);
+	vdev->config->del_vqs(vdev);
 
 	for (i = 0; snd->substreams && i < snd->nsubstreams; ++i) {
 		struct virtio_pcm_substream *vss = &snd->substreams[i];
@@ -383,8 +383,8 @@ static int virtsnd_freeze(struct virtio_device *vdev)
 	virtsnd_disable_event_vq(snd);
 	virtsnd_ctl_msg_cancel_all(snd);
 
-	vdev->config->del_vqs(vdev);
 	virtio_reset_device(vdev);
+	vdev->config->del_vqs(vdev);
 
 	for (i = 0; i < snd->nsubstreams; ++i)
 		cancel_work_sync(&snd->substreams[i].elapsed_period);
-- 
2.43.0