app/testpmd: fix max Rx packet length for VLAN packet

[ upstream commit f6870a7 ]

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: 35b2d13 ("net: add rte prefix to ether defines")

Signed-off-by: Steve Yang <stevex.yang@intel.com>
Reviewed-by: Ferruh Yigit <ferruh.yigit@intel.com>

app/test-pmd/testpmd.c

@@ -1301,6 +1301,7 @@ 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;
@@ -1337,6 +1338,28 @@ 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;
+
+		/*
+		 * This is workaround to avoid resize max rx packet len.
+		 * Ethdev assumes jumbo frame size must be greater than
+		 * RTE_ETHER_MAX_LEN, and will resize 'max_rx_pkt_len' to
+		 * default value when it is greater than RTE_ETHER_MAX_LEN
+		 * for normal frame.
+		 */
+		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 &=