RE: [net-next 11/17] i40e: Add promiscuous on VLAN support

-----Original Message-----
From: Or Gerlitz [mailto:gerlitz.or@gmail.com]
Sent: Tuesday, October 20, 2015 8:47 AM
To: Rose, Gregory V
Cc: David Miller; Kirsher, Jeffrey T; Singhai, Anjali;
netdev@vger.kernel.org; nhorman@redhat.com; sassmann@redhat.com;
jogreene@redhat.com
Subject: Re: [net-next 11/17] i40e: Add promiscuous on VLAN support

On Tue, Oct 20, 2015 at 6:31 PM, Rose, Gregory V
[off-list ref] wrote:

quoted

quoted

quoted

NFV use cases require the ability to steer packets to VSIs by VLAN
tag alone while being in promiscuous mode for multicast and unicast
MAC addresses.  These two new functions support that ability.

Change-ID: Ifef704b07e0ee8a39d3c351dbd5dc83bb2f63c45
Signed-off-by: Greg Rose <redacted>
Tested-by: Andrew Bowers <redacted>
Signed-off-by: Jeff Kirsher <redacted>

quoted

The patch(es) that use these functions are not yet prepared.  We will

wait until they're ready to submit these patches.  Sorry for the confusion
but I was out on vacation and didn't have a chance to coordinate this with
Jeff.

quoted

We needed the VF trust code in the kernel before we could add in these

additional patches.  We can work with Anjali to get those now that the VF
trust feature is in the kernel.

Can you please explain your design for supporting VF promiscuous mode?

Sure.

Up until now Intel SR-IOV VF drivers have not been allowed to enter promiscuous mode due to security issues.  Now that the PF driver supports the netdev op to set a VF as "trusted" we will add code to the VF driver to request promiscuous mode if asked to enter promiscuous mode by the OS network stack, IFF_PROMISC. If the VF has been configured as trusted through the PF driver then the PF driver will go ahead and configure the VF for promiscuous mode operation.  It will be full promiscuous mode unless the user has configured VLAN filters.  In that case the promiscuous mode will affect MAC addresses but will still use VLAN tags to steer traffic to the correct VF(s).

This will allow a VF to accept any packet on a VLAN regardless of the MAC destination address and amounts to VLAN tag packet steering.  There are NFV use cases for this type of operation.

I hope this answers your question.  If not I'd be happy to provide more details.

- Greg