I recently decided that I wanted to create a zone with an exclusive IP instance, so that I could run IPsec (and specifically "punchin") in it. I have lots of NICs floating around, so I thought it would be trivial.
Turns out that all my NICs were GLDv2, and that IP instances requires GLDv3.
My solution? Conversion of mxfe (which were the cards I have in my system) to GLDv3. I figured it would be easier/faster than going out and buying a new Realtek card. And it would have been if not for one really annoying problem in mcopymsg() (see my previous post for that rant.)
Anyway, mxfe is humming away nicely now as a GLDv3 NIC on my system. I even got VLANs working with full MTU frames. Yay. I filed PSARC 2007/291 today, if you're interested in it. I'll post the driver sources up somewhere shortly.
(On another note, mxfe and afe are "suboptimal" drivers... they just blindly bcopy data, do nothing to reduce tx interrupts, and basically violate all the normal rules for making performant NIC drivers. But they work pretty well, for all that.)