PG_FOW
npte |= PG_FOR | PG_FOW | PG_FOE;
npte |= PG_FOW;
pmap_changebit(pg, PG_FOW, ~0, cpu_id);
pmap_changebit(pg, PG_FOR | PG_FOW | PG_FOE, ~0, cpu_id);
if (!(*pte & PG_FOW)) {
faultoff = PG_FOR | PG_FOW;