why do we still need bootmem allocator?

[Michal Hocko]

Hi,
I am wondering why do we still keep mm/bootmem.c when most architectures
already moved to nobootmem. Is there any fundamental reason why others
cannot or this is just a matter of work? Btw. what really needs to be
done? Btw. is there any documentation telling us what needs to be done
in that regards?
-- 
Michal Hocko
SUSE Labs