Hi Guenter,

Interesting question. Does the underlying network device support VLAN HW
acceleration (NETIF_F_HW_VLAN_CTAG_RX, NETIF_F_HW_VLAN_CTAG_TX) ?

Yes, in our case, it's an IGB device.

I also set the DSA slave_dev->features and slave_dev->vlan_features to
master->vlan_features | NETIF_F_VLAN_FEATURES | NETIF_F_HW_SWITCH_OFFLOAD, 
not sure if it is good or not.

If yes, the dsa code may need to move the tag into the header.
If we are lucky, a call to vlan_hwaccel_push_inside() might do it.

Thanks, I'm currently looking into it and doing some tests, I'm coming back to 
you asap.

Do you have some vlan dsa code to share, by any chance ? That might
save me some time, as I am looking into it as well.

Yes, I am about the send an RFC for fully integrated 802.1q VLAN support on 
Marvell 88E6352 devices.

Thanks,
-v