PVF_MULTCLR
KASSERT(!(md->pvh_attrs & PVF_MULTCLR));
md->pvh_attrs |= PVF_MULTCLR;
&& (md->pvh_attrs & PVF_MULTCLR)) {
KASSERT(!(md->pvh_attrs & PVF_MULTCLR));
if (md->pvh_attrs & PVF_MULTCLR) {
KASSERT(!(md->pvh_attrs & PVF_MULTCLR));
md->pvh_attrs |= PVF_MULTCLR;
KASSERT(!(md->pvh_attrs & PVF_MULTCLR));
if (md->pvh_attrs & PVF_MULTCLR) {
md->pvh_attrs &= ~PVF_MULTCLR;
md->pvh_attrs &= ~PVF_MULTCLR;
} else if (md->pvh_attrs & PVF_MULTCLR) {