diff mbox series

[17/78] virtio: update queue size on guest write

Message ID 20200616141547.24664-18-mdroth@linux.vnet.ibm.com
State New
Headers show
Series Patch Round-up for stable 4.2.1, freeze on 2020-06-22 | expand

Commit Message

Michael Roth June 16, 2020, 2:14 p.m. UTC 
From: "Michael S. Tsirkin" <mst@redhat.com>

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 <rkagan@virtuozzo.com>
Suggested-by: Denis Plotnikov <dplotnikov@virtuozzo.com>
Cc: qemu-stable@nongnu.org
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
(cherry picked from commit d0c5f643383b9e84316f148affff368ac33d75b9)
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
---
 hw/virtio/virtio-pci.c | 2 ++
 1 file changed, 2 insertions(+)
diff mbox series

Patch

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,