PG_ROOT_L
#define PG_ROOT_SIZE (1UL << PG_ROOT_L) /* va range mapped by pp2d */
#define PG_ROOT_SHIFT PG_ROOT_L
#define PG_ROOT_NUM (PG_ROOT_H - PG_ROOT_L + 1)
#define PDIR_L1_H (PG_ROOT_L-1)