tests/vhost-user-bridge: workaround stale vring base

This patch is a similar solution to what Yuanhan Liu/Huawei Xie have
suggested for DPDK. When vubr quits (killed or crashed), a restart of
vubr would get stale vring base from QEMU. That would break the kernel
virtio net completely, making it non-work any more, unless a driver
reset is done.

So, instead of getting the stale vring base from QEMU, Huawei suggested
we could get a proper one from used->idx. This works because the queues
packets are processed in order.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Tested-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Reviewed-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Reviewed-by: Victor Kaplansky <victork@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This commit is contained in:
Marc-André Lureau 2016-06-06 18:45:01 +02:00 committed by Michael S. Tsirkin
parent aef8486ede
commit 523b018dde

View file

@ -946,6 +946,13 @@ vubr_set_vring_addr_exec(VubrDev *dev, VhostUserMsg *vmsg)
DPRINT(" vring_avail at %p\n", vq->avail);
vq->last_used_index = vq->used->idx;
if (vq->last_avail_index != vq->used->idx) {
DPRINT("Last avail index != used index: %d != %d, resuming",
vq->last_avail_index, vq->used->idx);
vq->last_avail_index = vq->used->idx;
}
return 0;
}