net/virtio: init MTU in case no control channel

The max_mtu is kept as zero in case no CRTL channel, which leads
to failure when calling virtio_mtu_set().

Signed-off-by: Zhike Wang <wangzhike@jd.com>
Acked-by: Zhiyong Yang <zhiyong.yang@intel.com>
Acked-by: Yuanhan Liu <yliu@fridaylinux.org>

diff --git a/drivers/net/virtio/virtio_ethdev.c b/drivers/net/virtio/virtio_ethdev.c
index ebb968c..954989e 100644 (file)
--- a/drivers/net/virtio/virtio_ethdev.c
+++ b/drivers/net/virtio/virtio_ethdev.c
@@ -1482,6 +1482,8 @@ virtio_init_device(struct rte_eth_dev *eth_dev, uint64_t req_features)
        } else {
                PMD_INIT_LOG(DEBUG, "config->max_virtqueue_pairs=1");
                hw->max_queue_pairs = 1;
+               hw->max_mtu = VIRTIO_MAX_RX_PKTLEN - ETHER_HDR_LEN -
+                       VLAN_TAG_LEN - hw->vtnet_hdr_size;
        }
 
        ret = virtio_alloc_queues(eth_dev);