PDIR_SLOT_EARLY
pml4e[PDIR_SLOT_EARLY] = (pd_entry_t)early_pte_pages | PG_V | PG_RW |
va = (vaddr_t)((PDIR_SLOT_EARLY * 512ULL) << L3_SHIFT) + off;
pml4e[PDIR_SLOT_EARLY] = 0;