Commit 734cbb5b authored Oct 29, 2014 by Guenter Roeck Committed by David S. Miller Oct 30, 2014

net: dsa: Don't set skb->protocol on outgoing tagged packets



Setting skb->protocol to a private protocol type may result in warning
messages such as
	e1000e 0000:00:19.0 em1: checksum_partial proto=dada!

This happens if the L3 protocol is IP or IPv6 and skb->ip_summed is set
to CHECKSUM_PARTIAL. Looking through the code, it appears that changing
skb->protocol for transmitted packets is not necessary and may actually
be harmful. For example, it prevents purposely unmodified (from a DSA
perspective) network drivers from properly setting up their transmit
checksum offload pointers since they inspect skb->protocol to set up the
IPv4 header or IPv6 header pointers. So don't unnecessarily change the
protocol field.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent 75fbfd33

net/dsa/tag_dsa.c

+0 −2

Original line number	Diff line number	Diff line
		@@ -63,8 +63,6 @@ static netdev_tx_t dsa_xmit(struct sk_buff skb, struct net_device dev)
		dsa_header[3] = 0x00;
		}

		skb->protocol = htons(ETH_P_DSA);

		skb->dev = p->parent->dst->master_netdev;
		dev_queue_xmit(skb);

net/dsa/tag_edsa.c

+0 −2

Original line number	Diff line number	Diff line
		@@ -76,8 +76,6 @@ static netdev_tx_t edsa_xmit(struct sk_buff skb, struct net_device dev)
		edsa_header[7] = 0x00;
		}

		skb->protocol = htons(ETH_P_EDSA);

		skb->dev = p->parent->dst->master_netdev;
		dev_queue_xmit(skb);

net/dsa/tag_trailer.c

+0 −2

Original line number	Diff line number	Diff line
		@@ -57,8 +57,6 @@ static netdev_tx_t trailer_xmit(struct sk_buff skb, struct net_device dev)
		trailer[2] = 0x10;
		trailer[3] = 0x00;

		nskb->protocol = htons(ETH_P_TRAILER);

		nskb->dev = p->parent->dst->master_netdev;
		dev_queue_xmit(nskb);

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