From c59f93d9a1e09e21e27f5bde7d8632a4d0503582 Mon Sep 17 00:00:00 2001 From: Bin Zheng Date: Fri, 10 Dec 2021 16:22:09 +0800 Subject: [PATCH] net/ixgbe: add vector Rx parameter check Under the circumstance that `rx_tail` wrap back to zero and the advance speed of `rx_tail` is greater than `rxrearm_start`, `rx_tail` will catch up with `rxrearm_start` and surpass it. This may cause some mbufs be reused by application. So we need to make some restrictions to ensure that `rx_tail` will not exceed `rxrearm_start`. e.g. RDH: 972 RDT: 991 rxrearm_nb: 991 rxrearm_start: 992 rx_tail: 959 RDH: 1004 RDT: 1023 rxrearm_nb: 991 rxrearm_start: 0 rx_tail: 991 RDH: 12 RDT: 31 rxrearm_nb: 991 rxrearm_start: 32 rx_tail: 1023 RDH: 31 RDT: 63 rxrearm_nb: 960 rxrearm_start: 64 rx_tail: 0 RDH: 95 RDT: 95 rxrearm_nb: 1016 rxrearm_start: 96 rx_tail: 88 RDH: 95 RDT: 127 rxrearm_nb: 991 rxrearm_start: 128 rx_tail: 95 ... RDH: 908 RDT: 927 rxrearm_nb: 991 rxrearm_start: 928 rx_tail: 895 RDH: 940 RDT: 959 rxrearm_nb: 991 rxrearm_start: 960 rx_tail: 927 RDH: 980 RDT: 991 rxrearm_nb: 991 rxrearm_start: 992 rx_tail: 959 RDH: 991 RDT: 991 rxrearm_nb: 1026 rxrearm_start: 992 rx_tail: 994 when `rx_tail` catches up with `rxrearm_start`, 2(994 - 992) mbufs be reused by application ! Bugzilla ID: 882 Fixes: 5a3cca342417 ("net/ixgbe: fix vector Rx") Cc: stable@dpdk.org Signed-off-by: Bin Zheng Acked-by: Leyi Rong Reviewed-by: Haiyue Wang Reviewed-by: Liang Ma --- drivers/net/ixgbe/ixgbe_rxtx_vec_sse.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/drivers/net/ixgbe/ixgbe_rxtx_vec_sse.c b/drivers/net/ixgbe/ixgbe_rxtx_vec_sse.c index c56f76b368..bb34b27168 100644 --- a/drivers/net/ixgbe/ixgbe_rxtx_vec_sse.c +++ b/drivers/net/ixgbe/ixgbe_rxtx_vec_sse.c @@ -364,6 +364,17 @@ _recv_raw_pkts_vec(struct ixgbe_rx_queue *rxq, struct rte_mbuf **rx_pkts, uint8_t vlan_flags; uint16_t udp_p_flag = 0; /* Rx Descriptor UDP header present */ + /* + * Under the circumstance that `rx_tail` wrap back to zero + * and the advance speed of `rx_tail` is greater than `rxrearm_start`, + * `rx_tail` will catch up with `rxrearm_start` and surpass it. + * This may cause some mbufs be reused by application. + * + * So we need to make some restrictions to ensure that + * `rx_tail` will not exceed `rxrearm_start`. + */ + nb_pkts = RTE_MIN(nb_pkts, RTE_IXGBE_RXQ_REARM_THRESH); + /* nb_pkts has to be floor-aligned to RTE_IXGBE_DESCS_PER_LOOP */ nb_pkts = RTE_ALIGN_FLOOR(nb_pkts, RTE_IXGBE_DESCS_PER_LOOP); -- 2.39.5