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>
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;
}