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charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 27.08.26 09:42, Paolo Abeni wrote: > On 8/26/26 11:02 PM, Florian Westphal wrote: >> Jakub Sitnicki wrote: > Still WRT optimizing skb_ext size, I think that it should be feasible to > optimize the layout proposed by Florian by taking in account that some > exts are 'mutually exclusive' i.e. on top of my head mptcp and bridge > should never be attached to the same skb, and I *guess* can_skb_ext is > mutually exclusive with most of the others. I would say with *all* of the others. CAN skbs only interact with ARPHDR_CAN netdevs containing a special ml_priv reference. And routing/forwarding is done by a CAN specific net/can/gw.c code. The only code outside net/can that looks into CAN skbs is: em_canid.c Ematch rule to match CAN frames according to their CAN IDs But I think this is not even relevant for CONFIG_NET_TC_SKB_EXT. > The layout could be adapted to such constraints, and there could be > run-time checks (under DEBUG_NET) to verify such constrains at skb_add > time leveraging `present_extensions` and a static matrix describing the > mutual exclusive status for all extensions. +1 Best regards, Oliver