On Mon, Oct 20, 2014 at 04:10:16PM +0300, Michael S. Tsirkin wrote:

On Mon, Oct 20, 2014 at 01:07:50PM +0100, Thomas Graf wrote:

quoted

On 10/13/14 at 10:50am, Michael S. Tsirkin wrote:

quoted

virtio spec requires drivers to set DRIVER_OK before using VQs.
This is set automatically after probe returns, virtio console violated this
rule by adding inbufs, which causes the VQ to be used directly within
probe.

To fix, call virtio_device_ready before using VQs.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
 drivers/char/virtio_console.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c
index b585b47..6ebe8f6 100644
--- a/drivers/char/virtio_console.c
+++ b/drivers/char/virtio_console.c

@@ -1449,6 +1449,8 @@ static int add_port(struct ports_device *portdev, u32 id)
 	spin_lock_init(&port->outvq_lock);
 	init_waitqueue_head(&port->waitqueue);
 
+	virtio_device_ready(portdev->vdev);
+
 	/* Fill the in_vq with buffers so the host can send us data. */
 	nr_added_bufs = fill_queue(port->in_vq, &port->inbuf_lock);
 	if (!nr_added_bufs) {

I see Cornelia sent a patch already.
I'd like to reproduce this though - could you send me
the command line please?

Nevermind, the trick is to add a port it seems:

-device virtio-serial -chardev socket,path=/tmp/c1,server,nowait,id=foo
-device virtserialport,chardev=foo,name=org.fedoraproject.port.0

works fine without -device virtserialport.

-- 
MST