On Wed, Dec 07, 2011 at 04:29:55PM +0530, Amit Shah wrote:

On (Wed) 07 Dec 2011 [12:43:24], Michael S. Tsirkin wrote:

quoted

quoted

diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c
index e14f5aa..fd2fd6f 100644
--- a/drivers/char/virtio_console.c
+++ b/drivers/char/virtio_console.c

@@ -1844,6 +1844,60 @@ static unsigned int features[] = {
 	VIRTIO_CONSOLE_F_MULTIPORT,
 };
 
+#ifdef CONFIG_PM
+static int virtcons_freeze(struct virtio_device *vdev)
+{
+	struct ports_device *portdev;
+	struct port *port;
+
+	portdev = vdev->priv;
+
+	vdev->config->reset(vdev);

So here, cancel_work_sync might still be running.
If it does run, might it try to access the device
config?  Could not determine this quickly, if yes it's a problem.

Similar to the other comment: I don't see why just resetting device
can cause config queue access to go bad.

		Amit

Hmm, not sure anymore. Sorry.