On Wed, Feb 09, 2022 at 11:51:58PM +0200, Vladimir Oltean wrote:

Re: title. Tail or trailing?

On Wed, Feb 09, 2022 at 06:13:11PM -0300, Luiz Angelo Daros de Luca wrote:

quoted

+static inline void rtl8_4_write_tag(struct sk_buff *skb, struct net_device *dev,
+				    char *tag)
 {
 	struct dsa_port *dp = dsa_slave_to_port(dev);
-	__be16 *tag;
-
-	skb_push(skb, RTL8_4_TAG_LEN);
-
-	dsa_alloc_etype_header(skb, RTL8_4_TAG_LEN);
-	tag = dsa_etype_header_pos_tx(skb);
+	__be16 *tag16 = (__be16 *)tag;

Can the tail tag be aligned to an odd offset? In that case, should you
access byte by byte, maybe? I'm not sure how arches handle this.

You should use get_unaligned_be16().

    Andrew