tree b055dd93fb446914a908ebec0829ce89df9b53c0
parent 3850d29fc40f3494a3e9c3aac45b6afe53526449
author Brian Foley <brian.foley@arm.com> 1348493622 +0100
committer Rusty Russell <rusty@rustcorp.com.au> 1348810516 +0930

virtio_mmio: Don't attempt to create empty virtqueues

If a virtio device reports a QueueNumMax of 0, vring_new_virtqueue()
doesn't check this, and thanks to an unsigned (i < num - 1) loop
guard, scribbles over memory when initialising the free list.

Avoid by not trying to create zero-descriptor queues, as there's no
way to do any I/O with one.

Signed-off-by: Brian Foley <brian.foley@arm.com>
Signed-off-by: Pawel Moll <pawel.moll@arm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>