On Sat, 24 Apr 2021 16:14:31 -0400 Michael Chan wrote:

+	features = vlan_features_check(skb, features);
+	if (!skb->encapsulation)
+		return features;
+
+	switch (vlan_get_protocol(skb)) {
+	case htons(ETH_P_IP):
+		l4_proto = ip_hdr(skb)->protocol;
+		break;
+	case htons(ETH_P_IPV6):
+		l4_proto = ipv6_hdr(skb)->nexthdr;
+		break;
+	default:
+		return features;
+	}
+
+	/* For UDP, we can only handle 1 Vxlan port and 1 Geneve port. */
+	if (l4_proto == IPPROTO_UDP) {
+		struct bnxt *bp = netdev_priv(dev);
+		__be16 udp_port = udp_hdr(skb)->dest;
+
+		if (udp_port != bp->vxlan_port && udp_port != bp->nge_port)
+			return features & ~(NETIF_F_CSUM_MASK |
+					    NETIF_F_GSO_MASK);
+	}
+	return features;

This is still written a little too much like a block list.

What if, for example it's a UDP tunnel but with extension headers?
Is there any particular case that is served by not writing it as:

	if (l4_proto == UDP && (port == bp->vxl_port ||
				port == bp->nge_port))
		return features;
	return features & ~(CSUM | GSO);
?

Sorry for not realizing this earlier.