[ovs-dev] [PATCH 0/5 V6] Add 802.1ad (qinq) support

[Ben Pfaff]

My big comment on this series is that I don't understand how this is
going to interact with OpenFlow, especially in a backward-compatibility
sense.

Here's an example: in OpenFlow 1.0, one can drop all double-tagged VLANs
by matching on packets that have a Ethertype of 0x88aa or 0x8100, since
the second VLAN header shows up as the Ethertype.  After this patch
series, I guess that that will no longer be true.

Have you thought about these issues?