Re: [PATCH 1/2] if_link: Add VF multicast promiscuous mode control

["Bjørn Mork" <bjorn@mork.no>]

Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com> writes:

>> Why can't the ixgbevf driver just automatically signal the ixgbe driver
>> to enable multicast promiscuous mode whenever the list grows past the
>> limit?
>
> I had submitted a patch to change ixgbe and ixgbevf driver for this issue.
> https://lkml.org/lkml/2014/11/27/269
>
> The previous patch introduces API between ixgbe and ixgbevf driver to
> enable multicast promiscuous mode, and ixgbevf enables it automatically
> if the number of addresses is over than 30.
>
> I got some comment and I would like to clarify the point, but there was no
> answer.
> That's the reason I submitted this patch.

Thanks.  Yes, now I understand why you want to have a policy knob.

I still think the policy could select between "automatic"/"disallowed"
instead of "enabled"/"disabled", but that's a minor detail. Likewise is
the actual implemention of "automatic".  I think you could do that
within the current VF-PF protocol by overloading the MC address "count".

But a more generic question for netdev is: Does this VF policy API
really scale?

How many different VF policy tunables can you imaging add up over a few
years and drivers.  Currently each policy flag require its own ndo hook.
I probably don't have much to say here, but IMHO this scheme had already
failed when .ndo_set_vf_spoofchk was added..


Bjørn