Commit b91e8212 authored by Michael Chan's avatar Michael Chan Committed by Jakub Kicinski
Browse files

bnxt_en: Linearize TX SKB if the fragments exceed the max 



If skb_shinfo(skb)->nr_frags excceds what the chip can support,
linearize the SKB and warn once to let the user know.
net.core.max_skb_frags can be lowered, for example, to avoid the
issue.

Fixes: 3948b059 ("net: introduce a config option to tweak MAX_SKB_FRAGS")
Reviewed-by: default avatarSomnath Kotur <somnath.kotur@broadcom.com>
Reviewed-by: default avatarKalesh AP <kalesh-anakkur.purayil@broadcom.com>
Reviewed-by: default avatarAndy Gospodarek <andrew.gospodarek@broadcom.com>
Signed-off-by: default avatarMichael Chan <michael.chan@broadcom.com>
Reviewed-by: default avatarSimon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250321211639.3812992-3-michael.chan@broadcom.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 107b25db

drivers/net/ethernet/broadcom/bnxt/bnxt.c

+11 −0
Original line number Diff line number Diff line
@@ -485,6 +485,17 @@ static netdev_tx_t bnxt_start_xmit(struct sk_buff *skb, struct net_device *dev) 
	txr = &bp->tx_ring[bp->tx_ring_map[i]];

	prod = txr->tx_prod;



#if (MAX_SKB_FRAGS > TX_MAX_FRAGS)

	if (skb_shinfo(skb)->nr_frags > TX_MAX_FRAGS) {

		netdev_warn_once(dev, "SKB has too many (%d) fragments, max supported is %d.  SKB will be linearized.\n",

				 skb_shinfo(skb)->nr_frags, TX_MAX_FRAGS);

		if (skb_linearize(skb)) {

			dev_kfree_skb_any(skb);

			dev_core_stats_tx_dropped_inc(dev);

			return NETDEV_TX_OK;

		}

	}

#endif

	free_size = bnxt_tx_avail(bp, txr);

	if (unlikely(free_size < skb_shinfo(skb)->nr_frags + 2)) {

		/* We must have raced with NAPI cleanup */

drivers/net/ethernet/broadcom/bnxt/bnxt.h

+4 −0
Original line number Diff line number Diff line
@@ -84,6 +84,10 @@ struct tx_bd { 


#define TX_BD_CNT(n)	(((n) << TX_BD_FLAGS_BD_CNT_SHIFT) & TX_BD_FLAGS_BD_CNT)



#define TX_MAX_BD_CNT	32



#define TX_MAX_FRAGS		(TX_MAX_BD_CNT - 2)



struct tx_bd_ext {

	__le32 tx_bd_hsize_lflags;

	#define TX_BD_FLAGS_TCP_UDP_CHKSUM			(1 << 0)