-"remap_page_range()" mm function wants the physical address of the memory to
-be remapped (the memory management layer doesn't know about devices outside
-the CPU, so it shouldn't need to know about "bus addresses" etc).
+"remap_pfn_range()" mm function wants the physical address of the memory to
+be remapped as measured in units of pages, a.k.a. the pfn (the memory
+management layer doesn't know about devices outside the CPU, so it
+shouldn't need to know about "bus addresses" etc).