[dpdk-dev] [PATCH v7 1/1] app/testpmd: fix max rx packet length for VLAN packets

[SteveX Yang]

When the max rx packet length is smaller than the sum of mtu size and
ether overhead size, it should be enlarged, otherwise the VLAN packets
will be dropped.

Fixes: 35b2d13fd6fd ("net: add rte prefix to ether defines")

Signed-off-by: SteveX Yang <stevex.yang at intel.com>
---
 app/test-pmd/testpmd.c | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/app/test-pmd/testpmd.c b/app/test-pmd/testpmd.c
index 33fc0fddf..754066950 100644
--- a/app/test-pmd/testpmd.c
+++ b/app/test-pmd/testpmd.c
@@ -1421,6 +1421,7 @@ init_config(void)
 	struct rte_gro_param gro_param;
 	uint32_t gso_types;
 	uint16_t data_size;
+	uint16_t overhead_len;
 	bool warning = 0;
 	int k;
 	int ret;
@@ -1457,6 +1458,25 @@ init_config(void)
 			rte_exit(EXIT_FAILURE,
 				 "rte_eth_dev_info_get() failed\n");
 
+		/* Update the max_rx_pkt_len to have MTU as RTE_ETHER_MTU */
+		if (port->dev_info.max_rx_pktlen && port->dev_info.max_mtu)
+			overhead_len = port->dev_info.max_rx_pktlen -
+				port->dev_info.max_mtu;
+		else
+			overhead_len = RTE_ETHER_HDR_LEN + RTE_ETHER_CRC_LEN;
+
+		port->dev_conf.rxmode.max_rx_pkt_len =
+						RTE_ETHER_MTU + overhead_len;
+
+		/*
+		 * Workaround: only adapt to RTE_ETHER_MAX_LEN as
+		 * jumbo frame condition.
+		 */
+		if (port->dev_conf.rxmode.max_rx_pkt_len > RTE_ETHER_MAX_LEN) {
+			port->dev_conf.rxmode.offloads |=
+						DEV_RX_OFFLOAD_JUMBO_FRAME;
+		}
+
 		if (!(port->dev_info.tx_offload_capa &
 		      DEV_TX_OFFLOAD_MBUF_FAST_FREE))
 			port->dev_conf.txmode.offloads &=
-- 
2.17.1