From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andrew Lunn <andrew@lunn.ch>
Subject: Re: [Query]: DSA Understanding
Date: Mon, 13 Aug 2018 15:38:17 +0200
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> > I agree, this should be padding packets correctly, can you still
> > instrument cpsw to make sure that what comes to its ndo_start_xmit() is
> > ETH_ZLEN + tag_len or more?
> >
> Yes I can confirm the skb->len is always >= 62 (ETH_ZLEN + 2)

Which switch are you using?

Marvell switches use either 4 or 8 bytes of tag. Broadcom has 4, KSZ
has 1 for packets going to the switch, lan9303 has 4, mtd uses 4, qca
has 2.

    Andrew