pmap_change_prot
int pmap_change_prot(void *, vm_size_t, vm_prot_t);
int pmap_change_prot(void *va, vm_size_t size, vm_prot_t prot);
error = pmap_change_prot(ef->address + phdr->p_vaddr,
error = pmap_change_prot((void *)start, end - start, prot);