[Qemu-devel] [PATCH 0/2] virtio-mmio: fixes to QueueNum, QueueNumMax

[Peter Maydell <peter.maydell@linaro.org>]

These patches fix a couple of bugs in virtio-mmio's
handling of the registers that deal with the queue size:

 * as mst points out, letting the guest flip a queue between
   "exists" and "doesn't exist" is a bad idea
 * QueueNumMax wasn't reading the correct value for nonexistent
   queues

This doesn't include any change to the behaviour of queuesize
on reset (discussed in other thread); the current behaviour is
not a problem for well-behaved guests, and safe in the face
of badly-behaved guests, and currently improving the reset
behaviour is blocked by an unrelated bug.

Peter Maydell (2):
  hw/virtio/virtio: Don't allow guests to add/remove queues
  hw/virtio/virtio-mmio: Make QueueNumMax read 0 for unavailable queues

 hw/virtio/virtio-mmio.c |    3 +++
 hw/virtio/virtio.c      |   10 +++++++---
 2 files changed, 10 insertions(+), 3 deletions(-)

-- 
1.7.9.5