[ovs-dev] [PATCH net-next 4/7] openvswitch: add ipv6 'set' action

[Jesse Gross]

On Tue, Dec 11, 2012 at 7:14 PM, Tom Herbert <therbert at google.com> wrote:
>> This patch adds ipv6 set action functionality. It allows to change
>> traffic class, flow label, hop-limit, ipv6 source and destination
>> address fields.
>>
> I have to wonder about these patches and the underlying design
> direction.  Aren't these sort of things and more already implemented
> by IPtables but in a modular and extensible fashion?  Has there been
> any thought into hooking OVS to IP tables to leverage all the existing
> functionality?

At an implementation level, the goal is definitely to share as much
code as possible.  Some of that was obviously done to support this
patch and I'm sure there are more areas where it could be taken
further.

At a more conceptual level we've explored this path a number of times
and it's never been attractive since it has a tendency to drag more
OVS code into other parts of the kernel and generally make things
worse for everybody.  Of course, it's hard to say without knowing what
you're thinking.  Do you have a specific proposal?