On 1/14/26 7:07 PM, Eric Dumazet wrote:

quoted

diff --git a/net/core/dev.c b/net/core/dev.c
index c711da335510..6154f306ed76 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c

@@ -3788,8 +3788,10 @@ static netdev_features_t gso_features_check(const struct sk_buff *skb,
                struct iphdr *iph = skb->encapsulation ?
                                    inner_ip_hdr(skb) : ip_hdr(skb);

-               if (!(iph->frag_off & htons(IP_DF)))
+               if (!(iph->frag_off & htons(IP_DF))) {
                        features &= ~NETIF_F_TSO_MANGLEID;

Nit : We could avoid the above line, if we always make sure
NETIF_F_TSO_MANGLEID is set in dev->mangleid_features

I thinks it makes a lot of sense. register_netdevice() could ensure such
 this constraint is respected; I'll add the following in the next
iteration and I will update the chunk here accordingly.

Thanks!

Paolo
---

diff --git a/net/core/dev.c b/net/core/dev.c
index c711da335510..a028ef1a3bcf 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c

@@ -11372,6 +11372,12 @@ int register_netdevice(struct net_device *dev)
 	if (dev->hw_enc_features & NETIF_F_TSO)
 		dev->hw_enc_features |= NETIF_F_TSO_MANGLEID;

+	/* Any mangleid feature disables TSO_MANGLEID; including the latter
+	 * in mangleid_features allows for better code in the fastpath.
+	 */
+	if (dev->mangleid_features)
+		dev->mangleid_features |= NETIF_F_TSO_MANGLEID;
+
 	/* Make NETIF_F_HIGHDMA inheritable to VLAN devices.
 	 */
 	dev->vlan_features |= NETIF_F_HIGHDMA;