Hi Linus, On Tue, 19 Dec 2023 15:19:45 +0100 Linus Walleij <linus.walleij@xxxxxxxxxx> wrote: > On Tue, Dec 19, 2023 at 2:07 PM Maxime Chevallier > <maxime.chevallier@xxxxxxxxxxx> wrote: > > > So it looks like an acceptable solution would be something along the > > lines of what Linus is suggesting here : > > > > https://lore.kernel.org/netdev/20231216-new-gemini-ethernet-regression-v2-2-64c269413dfa@xxxxxxxxxx/ > > > > If so, maybe it's worth adding a new helper for that check ? > > Yeah it's a bit annoying when skb->protocol is not == ethertype of buffer. > > I can certainly add a helper such as skb_eth_raw_ethertype() > to <linux/if_ether.h> that will inspect the actual ethertype in > skb->data. > > It's the most straight-forward approach. Agreed :) > We could also add something like bool custom_ethertype; to > struct sk_buff and set that to true if the tagger adds a custom > ethertype. But I don't know how the network developers feel about > that. I don't think this would be OK, first because sk_buff is pretty sensitive when it comes to cache alignment, adding things for this kind of use-cases isn't necessarily a good idea. Moreover, populating this flag isn't going to be straightforward as well. I guess some ethertype would be compatible with checksum engines, while other wouldn't, so probably what 'custom_ethertype' means will depend on the MAC driver. >From my point of view the first approach would indeed be better. Thanks, Maxime
