PAGE_FRAME_L48_WIDTH_BYTES
ptr += PAGE_FRAME_L48_WIDTH_BYTES;
ptr += PAGE_FRAME_L48_WIDTH_BYTES;
ptr += PAGE_FRAME_L48_WIDTH_BYTES;
ptr += PAGE_FRAME_L48_WIDTH_BYTES;
#define PAGE_FRAME_L48_WIDTH_BITS (PAGE_FRAME_L48_WIDTH_BYTES * 8)