From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH] macvlan: fix oops with vlan-on-top and HW_VLAN_CTAG_TX
 lowerdev
Date: Sat, 04 Jan 2014 20:13:33 -0500 (EST)
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From: Florian Westphal <fw@strlen.de>
Date: Sat, 4 Jan 2014 14:51:32 +0100

> Archeology exercise #1 digs up 3b04ddde02c in linux.git, which
> creats header_ops->rebuild, from the old  dev->rebuild_header.
> 
> Exercise #2 then finds commit 275513d2e1c78 in netdev-vger-cvs.git tree.
> Quote from commit message:
> 
>         - dev->rebuild_header WILL DISAPPEAR. All the code
>           relying on its existance is wrong, though still works.
> 
> Alexey calling from 1997 ;-)

These protocols which use the broken ARP ops are special, the
problem is that they do things like send packets out when their
header ops are invoked.

It's non-trivial to undo this design, and these aren't easy protocols
to test.

That's why we've had this compat stuff for them for more than a
decade.