[dpdk-dev] [PATCH v2 1/2] net/af_packet: fix driver init with default MTU

Ferruh Yigit ferruh.yigit at intel.com
Wed Oct 27 11:14:28 CEST 2021


Driver is using 'ETH_FRAME_LEN' Linux defined value as max frame length,
which doesn't include FCS (4 bytes CRC). But ethdev by default uses
frame size with FCS when application doesn't define any explicit value.

As a result device configuration fails because device is tried to be
configured with a frame size length that is bigger than what device
reported as supported. Device reports as max supported frame size is
1514 but configured value is 1518.

Instead use DPDK macro, 'RTE_ETHER_MAX_LEN', that includes FCS in the
driver to report the max supported frame size, this matches to the
initial intention.

Fixes: 1bb4a528c41f ("ethdev: fix max Rx packet length")

Reported-by: Andrew Rybchenko <andrew.rybchenko at oktetlabs.ru>
Signed-off-by: Ferruh Yigit <ferruh.yigit at intel.com>
---
v2:
* Remove unnecessary cast
---
 drivers/net/af_packet/rte_eth_af_packet.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/af_packet/rte_eth_af_packet.c b/drivers/net/af_packet/rte_eth_af_packet.c
index 559f5a03e509..cea7091c0639 100644
--- a/drivers/net/af_packet/rte_eth_af_packet.c
+++ b/drivers/net/af_packet/rte_eth_af_packet.c
@@ -342,7 +342,7 @@ eth_dev_info(struct rte_eth_dev *dev, struct rte_eth_dev_info *dev_info)
 
 	dev_info->if_index = internals->if_index;
 	dev_info->max_mac_addrs = 1;
-	dev_info->max_rx_pktlen = (uint32_t)ETH_FRAME_LEN;
+	dev_info->max_rx_pktlen = RTE_ETHER_MAX_LEN;
 	dev_info->max_rx_queues = (uint16_t)internals->nb_queues;
 	dev_info->max_tx_queues = (uint16_t)internals->nb_queues;
 	dev_info->min_rx_bufsize = 0;
-- 
2.31.1



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