Re: [PATCH net] ppp: linearize bridged packets when required

[Eric Dumazet]

Le jeu. 22 oct. 2026 à 04:18, Qingfang Deng <qingfang.deng@xxxxxxxxx> a écrit :
>
> On 2026/10/22 1:55, Eric Dumazet wrote:
> >> What about NETIF_F_FRAGLIST?
> > I do not see your point. Can you elaborate?
> >
> > There’s also nothing left to gain on fraglist packets.
> >
> > SKB_GSO_FRAGLIST packets already go through skb_segment_list(),
> > which just unchains the original skbs without copying, as the fraglist
> > test run showed.
> >
> > Frag_list skbs that aren’t fraglist GRO go through skb_segment(),
> > which with NETIF_F_SG already shares the pages of the chained skbs
> > instead of copying them.
>
> I've run selftests and confirmed that NETIF_F_FRAGLIST is unnecessary here.
>
> One extra finding: passing NETIF_F_SG conditionally can avoid an extra
> reallocation in skb_linearize().
>
> segs = skb_gso_segment(skb, chan->direct_xmit ? NETIF_F_SG : 0);

Yep, I can do this, thanks.

I was hesitant to duplicate the logic for something that has never
worked in the past,
and at very low rates, unless in emulators/fuzzers perhaps.