hi,

> I don't think uvm_km_free() would actually need to be told which flags were
> passed to uvm_km_kmemalloc(), it can probably figure everything out from
> the contents of the map.

i don't think keeping more info in the lower layer is a good idea
because
- it prevents map_entry merge between different allocation types and
  thus increases search cost.
- it's redundant.  (callers of uvm_km_free should know the type of the entry.)

YAMAMOTO Takashi