Check if it has already been vlan-tagged packet, if true, avoid inserting a duplicated vlan tag into it.
This is a possible case when guest has the capability of inserting vlan tag. Signed-off-by: Changchun Ouyang <changchun.ouyang at intel.com> --- examples/vhost/main.c | 18 ++++++++++++++---- 1 file changed, 14 insertions(+), 4 deletions(-) diff --git a/examples/vhost/main.c b/examples/vhost/main.c index 1f1edbe..a7e623e 100644 --- a/examples/vhost/main.c +++ b/examples/vhost/main.c @@ -1120,6 +1120,7 @@ virtio_tx_route(struct vhost_dev *vdev, struct rte_mbuf *m, uint16_t vlan_tag) unsigned len, ret, offset = 0; const uint16_t lcore_id = rte_lcore_id(); struct virtio_net *dev = vdev->dev; + struct ether_hdr *nh; /*check if destination is local VM*/ if ((vm2vm_mode == VM2VM_SOFTWARE) && (virtio_tx_local(vdev, m) == 0)) { @@ -1141,12 +1142,21 @@ virtio_tx_route(struct vhost_dev *vdev, struct rte_mbuf *m, uint16_t vlan_tag) tx_q = &lcore_tx_queue[lcore_id]; len = tx_q->len; - m->ol_flags = PKT_TX_VLAN_PKT; + nh = rte_pktmbuf_mtod(m, struct ether_hdr *); + if (unlikely(nh->ether_type == rte_cpu_to_be_16(ETHER_TYPE_VLAN))) { + /* Guest has inserted the vlan tag. */ + struct vlan_hdr *vh = (struct vlan_hdr *) (nh + 1); + uint16_t vlan_tag_be = rte_cpu_to_be_16(vlan_tag); + if (vh->vlan_tci != vlan_tag_be) + vh->vlan_tci = vlan_tag_be; + } else { + m->ol_flags = PKT_TX_VLAN_PKT; - m->data_len += offset; - m->pkt_len += offset; + m->data_len += offset; + m->pkt_len += offset; - m->vlan_tci = vlan_tag; + m->vlan_tci = vlan_tag; + } tx_q->m_table[len] = m; len++; -- 1.8.4.2