From mathcomp.ssreflect Require Import ssreflect ssrbool ssrnat ssrfun eqtype seq fintype finfun.
Set Implicit Arguments.
Definition bnd_from_init m := bounded_maps.bounded_map (snd (getMaxPerm m)) /\ (Mem.mem_access m).1 = fun z k => None.
Definition bounded_mem (m: mem) := bounded_maps.bounded_map (snd (getMaxPerm m)) .

Lemma drop_perm_bounded:
forall m b lo hi P m',
bounded_mem m ->
Mem.drop_perm m b lo hi P = Some m' ->
bounded_mem m'.