Re: [PATCH v3 4/5] net: dsa: add support for Atheros AR9331 TAG format
From: Andrew Lunn <andrew@lunn.ch>
Date: 2019-10-21 15:49:15
Also in:
linux-devicetree, linux-mips, lkml
+static struct sk_buff *ar9331_tag_rcv(struct sk_buff *skb,
+ struct net_device *ndev,
+ struct packet_type *pt)
+{
+ u8 ver, port;
+ u16 hdr;
+
+ if (unlikely(!pskb_may_pull(skb, AR9331_HDR_LEN)))
+ return NULL;
+
+ hdr = le16_to_cpu(*(__le16 *)skb_mac_header(skb));
+
+ ver = FIELD_GET(AR9331_HDR_VERSION_MASK, hdr);
+ if (unlikely(ver != AR9331_HDR_VERSION)) {
+ netdev_warn_once(ndev, "%s:%i wrong header version 0x%2x\n",
+ __func__, __LINE__, hdr);
+ return NULL;
+ }
+
+ if (unlikely(hdr & AR9331_HDR_FROM_CPU)) {
+ netdev_warn_once(ndev, "%s:%i packet should not be from cpu 0x%2x\n",
+ __func__, __LINE__, hdr);
+ return NULL;
+ }
+
+ skb_pull(skb, AR9331_HDR_LEN);
+ skb_set_mac_header(skb, -ETH_HLEN);
No other tag driver calls skb_set_mac_header(). Also, the -ETH_HLEN
looks odd, give you have just pulled off AR9331_HDR_LEN?
What other tag drivers use is skb_pull_rcsum().
Andrew