Re: [PATCH] net: linearizing skb when downgrade gso_size

From: Fred Li
Date: Fri Jul 12 2024 - 04:17:50 EST


> No need for ternary statement.
>
> Instead of the complex test in skb_is_nonsg, can we just assume that
> alignment will be off if having frag_list and changing gso_size.
>
> The same will apply to bpf_skb_net_shrink too.

increase gso_size may be no problem and we can use BPF_F_ADJ_ROOM_FIXED_GSO
to avoid update gso_size when shrink.

>
> Not sure that it is okay to linearize inside a BPF helper function.
> Hopefully bpf experts can chime in on that.

Thanks

Fred Li