If number of TX queues are set to 1 we get a NULL pointer dereference during XDP_TX. ~# ethtool -L eth0 tx 1 ~# ./xdp-trafficgen udp -A <ipv6-src> -a <ipv6-dst> eth0 -t 2 Transmitting on eth0 (ifindex 2) [ 241.135257] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000030 Fix this by using actual TX queues instead of max TX queues when picking the TX channel in am65_cpsw_ndo_xdp_xmit(). Fixes: 8acacc40f733 ("net: ethernet: ti: am65-cpsw: Add minimal XDP support") Signed-off-by: Roger Quadros <rogerq@xxxxxxxxxx> --- drivers/net/ethernet/ti/am65-cpsw-nuss.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/ti/am65-cpsw-nuss.c b/drivers/net/ethernet/ti/am65-cpsw-nuss.c index 9fd2ba26716c..03577a008df2 100644 --- a/drivers/net/ethernet/ti/am65-cpsw-nuss.c +++ b/drivers/net/ethernet/ti/am65-cpsw-nuss.c @@ -1924,12 +1924,13 @@ static int am65_cpsw_ndo_bpf(struct net_device *ndev, struct netdev_bpf *bpf) static int am65_cpsw_ndo_xdp_xmit(struct net_device *ndev, int n, struct xdp_frame **frames, u32 flags) { + struct am65_cpsw_common *common = am65_ndev_to_common(ndev); struct am65_cpsw_tx_chn *tx_chn; struct netdev_queue *netif_txq; int cpu = smp_processor_id(); int i, nxmit = 0; - tx_chn = &am65_ndev_to_common(ndev)->tx_chns[cpu % AM65_CPSW_MAX_TX_QUEUES]; + tx_chn = &common->tx_chns[cpu % common->tx_ch_num]; netif_txq = netdev_get_tx_queue(ndev, tx_chn->id); __netif_tx_lock(netif_txq, cpu); -- 2.34.1