On Fri, Mar 21, 2025 at 2:17 PM Michael Chan [off-list ref] wrote:
quoted hunk ↗ jump to hunk
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: 3948b05950fd ("net: introduce a config option to tweak MAX_SKB_FRAGS")
Reviewed-by: Somnath Kotur <redacted>
Reviewed-by: Kalesh AP <kalesh-anakkur.purayil@broadcom.com>
Reviewed-by: Andy Gospodarek <redacted>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
---
drivers/net/ethernet/broadcom/bnxt/bnxt.c | 11 +++++++++++
drivers/net/ethernet/broadcom/bnxt/bnxt.h | 4 ++++
2 files changed, 15 insertions(+)
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
index 158e9789c1f4..2cd79b59cf00 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
@@ -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
Hi Michael
Sorry for the delay. I just saw your patch.
GSO would be more efficient and less likely to fail under memory pressure.
Could you test the following patch for me ?
Thanks !
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
index 3a9ffaaf60ae810bf8772b0cad0da45bc4ec9a05..c2a831efa969742711f5afdc7b24ba2c450cc595
100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
@@ -13787,6 +13787,10 @@ static netdev_features_t
bnxt_features_check(struct sk_buff *skb,
u8 *l4_proto;
features = vlan_features_check(skb, features);
+#if MAX_SKB_FRAGS > TX_MAX_FRAGS
+ if (skb_shinfo(skb)->nr_frags > TX_MAX_FRAGS)
+ features &= ~NETIF_F_GSO_MASK;
+#endif
switch (vlan_get_protocol(skb)) {
case htons(ETH_P_IP):
if (!skb->encapsulation)