Created attachment 154834 [details]
After some back and forth on the mailing list (freebsd-net) Hans Petter Selasky came up with the attached patch which I tested successfully.
I've noticed that mbuf tags aren't being copied from the leading fragment (header) to the subsequent fragment packets. In other words, one would expect that all fragments of a packet are carrying the same tags that were set on the original packet. I have built a simple test were I use ipfw with ALTQ and sent large packet (bigger then MTU) off that BSD machine. I have observed that the leading fragment (m0) packet is going through the right class although the next fragments are hitting the default class for unclassified packets.
I'll process this issue in the coming week. Thank you!
batch change of PRs untouched in 2018 marked "in progress" back to open.
This was committed in r280991.