Messages in this thread | | | From | Linus Walleij <> | Date | Tue, 31 Oct 2023 23:44:58 +0100 | Subject | Re: [PATCH net v2] net: dsa: tag_rtl4_a: Bump min packet size |
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On Mon, Oct 30, 2023 at 3:16 PM Vladimir Oltean <olteanv@gmail.com> wrote:
> if (skb->len >= 1496) > __skb_put_padto(skb, 1518, false); > > (...) > > skb_push(skb, 4); > > which means that here, skb->len will be 1522, if it was originally 1496. > So the code adds 26 extra octets, and only 4 of those are legitimate (a tag). > The rest is absolutely unexplained, which means that until there is a > valid explanation for them:
Indeed only 4 of them are needed, I tested to add 4 bytes on the tail for > 1496 and it works.
I'll send a new version.
However that its "tag" is bogus since the extra tail isn't needed before the paket becomes 1496 bytes, i.e. 1500 bytes including the tag. It has a logic to it but ... yeah. All I can think of is bad VHDL in the switch.
Yours, Linus Walleij
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