In the function virtqueue_enqueue_xmit(), when can_push is true,
vtnet_hdr_size is added to pkt_len by calling rte_pktmbuf_prepend.
which is wrong for pkt stats, virtio header length should be subtracted
before calling stats function.
Fixes: 58169a9c8153 ("net/virtio: support Tx checksum offload")
Cc: sta...@dpdk.org
Cc: y...@fridaylinux.org
Cc: maxime.coque...@redhat.com
Signed-off-by: Zhiyong Yang <zhiyong.y...@intel.com>
Reviewed-by: Maxime Coquelin <maxime.coque...@redhat.com>
---
Changes in V3:
Move code inside "if (can_push)" clause and simplify comments.
Changes in V2:
Put code in the function virtqueue_enqueue_xmit() according to
yuanhan's comments.
drivers/net/virtio/virtio_rxtx.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/drivers/net/virtio/virtio_rxtx.c b/drivers/net/virtio/virtio_rxtx.c
index 2cf82fef4..ac4055d45 100644
--- a/drivers/net/virtio/virtio_rxtx.c
+++ b/drivers/net/virtio/virtio_rxtx.c
@@ -299,6 +299,10 @@ virtqueue_enqueue_xmit(struct virtnet_tx *txvq, struct
rte_mbuf *cookie,
/* prepend cannot fail, checked by caller */
hdr = (struct virtio_net_hdr *)
rte_pktmbuf_prepend(cookie, head_size);
+ /* rte_pktmbuf_prepend() counts the hdr size to the pkt length,
+ * which is wrong. Below subtract restores correct pkt size.
+ */
+ cookie->pkt_len -= head_size;
/* if offload disabled, it is not zeroed below, do it now */
if (offload == 0) {
ASSIGN_UNLESS_EQUAL(hdr->csum_start, 0);
--
2.13.3
