HN_RX_FLAG_ATTACHED
KASSERT((rxr->hn_rx_flags & HN_RX_FLAG_ATTACHED) == 0,
rxr->hn_rx_flags |= HN_RX_FLAG_ATTACHED;
KASSERT((rxr->hn_rx_flags & HN_RX_FLAG_ATTACHED),
rxr->hn_rx_flags &= ~HN_RX_FLAG_ATTACHED;
HN_RX_FLAG_ATTACHED) == 0,