Wow, it's been a while. Well, I ended up doing a crippled "map shm with 2M/4M pages" flag instead of MPSS, lazy_buddy has pretty much been killed, shared pagetables ended up getting done by dmc, and gang allocation stuff by mbligh. Ugh =(
At least -for_each_task went somewhere. Now I'm pretty much doing hugetlbfs maintenance and doing seek & destroy on various kinds of braindamage.