[PULL v3 07/32] virtio: update queue size on guest write

[Michael S. Tsirkin]

Some guests read back queue size after writing it.
Update the size immediatly upon write otherwise
they get confused.

In particular this is the case for seabios.

Reported-by: Roman Kagan <rka...@virtuozzo.com>
Suggested-by: Denis Plotnikov <dplotni...@virtuozzo.com>
Cc: qemu-sta...@nongnu.org
Signed-off-by: Michael S. Tsirkin <m...@redhat.com>
---
 hw/virtio/virtio-pci.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c
index c6b47a9c73..e5c759e19e 100644
--- a/hw/virtio/virtio-pci.c
+++ b/hw/virtio/virtio-pci.c
@@ -1256,6 +1256,8 @@ static void virtio_pci_common_write(void *opaque, hwaddr 
addr,
         break;
     case VIRTIO_PCI_COMMON_Q_SIZE:
         proxy->vqs[vdev->queue_sel].num = val;
+        virtio_queue_set_num(vdev, vdev->queue_sel,
+                             proxy->vqs[vdev->queue_sel].num);
         break;
     case VIRTIO_PCI_COMMON_Q_MSIX:
         msix_vector_unuse(&proxy->pci_dev,
-- 
MST