Re: [PATCH] net: dev_forward_skb(): Scrub packet's per-netns info only when crossing netns

[Shmulik Ladkani]

On Thu, 15 Mar 2018 08:01:03 -0700 (PDT) Liran Alon <liran.alon@xxxxxxxxxx> wrote:
> 
> I still think that default behavior should be to zero skb->mark only when skb
> cross netdevs in different netns.

But the previous default was scrub the mark in *both* xnet and non-xnet
situations.

Therefore, there might be users which RELY on this (strange) default
behavior in their same-netns-veth-pair setups.
Meaning, changing the default behavior might break their apps relying on
the former default behavior.

This is why the "disable mark scrubbing in non-xnet case" should be opt-in.

Regards,
Shmulik