From 985e7673c06af30b3cd6d0ebadbec885f81c9bfb Mon Sep 17 00:00:00 2001 From: Ciara Loftus Date: Fri, 22 Oct 2021 14:07:17 +0000 Subject: [PATCH] net/af_xdp: fix max Rx packet length Commit 1bb4a528c41f ("ethdev: fix max Rx packet length") clarified the expected usage of the max_rx_pktlen and max_mtu values and implemented some extra checks on these values to ensure they are sane. After this, the AF_XDP PMD fails to initialise. The value for max_rx_pktlen which represents the max size of the Ethernet frame was set to ETH_FRAME_LEN (1514) and the max_mtu which represents the size of the payload was set to the max size of the Ethernet frame. This did not make sense, as naturally the maximum frame size should be greater than the payload size. Fix this by setting the max_rx_pktlen equal to the max size of the Ethernet frame as expected, and the max MTU equal to the max_rx_pktlen less the overhead which is set to the size of an Ethernet header plus CRC. Fixes: 1bb4a528c41f ("ethdev: fix max Rx packet length") Signed-off-by: Ciara Loftus Reviewed-by: Ferruh Yigit --- drivers/net/af_xdp/rte_eth_af_xdp.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) diff --git a/drivers/net/af_xdp/rte_eth_af_xdp.c b/drivers/net/af_xdp/rte_eth_af_xdp.c index b362ccdcd3..8a3fa19043 100644 --- a/drivers/net/af_xdp/rte_eth_af_xdp.c +++ b/drivers/net/af_xdp/rte_eth_af_xdp.c @@ -78,6 +78,7 @@ RTE_LOG_REGISTER_DEFAULT(af_xdp_logtype, NOTICE); #define ETH_AF_XDP_RX_BATCH_SIZE XSK_RING_CONS__DEFAULT_NUM_DESCS #define ETH_AF_XDP_TX_BATCH_SIZE XSK_RING_CONS__DEFAULT_NUM_DESCS +#define ETH_AF_XDP_ETH_OVERHEAD (RTE_ETHER_HDR_LEN + RTE_ETHER_CRC_LEN) struct xsk_umem_info { struct xsk_umem *umem; @@ -826,19 +827,19 @@ 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 = ETH_FRAME_LEN; dev_info->max_rx_queues = internals->queue_cnt; dev_info->max_tx_queues = internals->queue_cnt; dev_info->min_mtu = RTE_ETHER_MIN_MTU; #if defined(XDP_UMEM_UNALIGNED_CHUNK_FLAG) - dev_info->max_mtu = getpagesize() - - sizeof(struct rte_mempool_objhdr) - - sizeof(struct rte_mbuf) - - RTE_PKTMBUF_HEADROOM - XDP_PACKET_HEADROOM; + dev_info->max_rx_pktlen = getpagesize() - + sizeof(struct rte_mempool_objhdr) - + sizeof(struct rte_mbuf) - + RTE_PKTMBUF_HEADROOM - XDP_PACKET_HEADROOM; #else - dev_info->max_mtu = ETH_AF_XDP_FRAME_SIZE - XDP_PACKET_HEADROOM; + dev_info->max_rx_pktlen = ETH_AF_XDP_FRAME_SIZE - XDP_PACKET_HEADROOM; #endif + dev_info->max_mtu = dev_info->max_rx_pktlen - ETH_AF_XDP_ETH_OVERHEAD; dev_info->default_rxportconf.burst_size = ETH_AF_XDP_DFLT_BUSY_BUDGET; dev_info->default_txportconf.burst_size = ETH_AF_XDP_DFLT_BUSY_BUDGET; -- 2.39.5