I faced this problem on 4.2.6, Debian Jessie, on PC Engines Alix6.
I applied the patch. It solved the problem.
Queue up for -stable?
Teco
>
> From: Francois Romieu
> Date: Thu, 15 Oct 2015 00:14:37 +0200
>
> > From: Andrej Ota
> >
> > Because eth_type_trans() consumes ethernet header worth
IP MTU and L2 MTU are different animals.
IMHO IP MTU is for fragmentation at sender of a link. There is no need dropping
IP packets at receiver with size > configured IP MTU. IP packets with size >
receiver L2 MTU will be dropped at sub-IP layer.
For this patch: if veth has some notion on L2 MT