ND_NA_FLAG_OVERRIDE
na->nd_na_flags_reserved & ND_NA_FLAG_OVERRIDE ?
na->nd_na_flags_reserved = ND_NA_FLAG_SOLICITED | ND_NA_FLAG_OVERRIDE;
na->nd_na_flags_reserved |= ND_NA_FLAG_OVERRIDE;
if (!(flag & ND_NA_FLAG_OVERRIDE) && ll_changed) {