-5 Doesn't check whether pointers are at or above PHYS_BASE
-2 Imperfect checking whether pointers are at or above PHYS_BASE
+3 Copies large chunks while properly observing page boundaries
-5 Doesn't check whether pointers are at or above PHYS_BASE
-2 Imperfect checking whether pointers are at or above PHYS_BASE
+3 Copies large chunks while properly observing page boundaries