diff --git a/sys/dev/netmap/if_em_netmap.h b/sys/dev/netmap/if_em_netmap.h
index b4b268ae11a..776f0e0ee82 100644
--- a/sys/dev/netmap/if_em_netmap.h
+++ b/sys/dev/netmap/if_em_netmap.h
@@ -292,6 +292,8 @@ em_netmap_rxsync(struct ifnet *ifp, u_int ring_nr, int do_lock)
 	l = rxr->next_to_check;
 	j = netmap_idx_n2k(kring, l);
 	if (netmap_no_pendintr || force_update) {
+		uint16_t slot_flags = kring->nkr_slot_flags;
+
 		for (n = 0; ; n++) {
 			struct e1000_rx_desc *curr = &rxr->rx_base[l];
 			uint32_t staterr = le32toh(curr->status);
@@ -299,6 +301,7 @@ em_netmap_rxsync(struct ifnet *ifp, u_int ring_nr, int do_lock)
 			if ((staterr & E1000_RXD_STAT_DD) == 0)
 				break;
 			ring->slot[j].len = le16toh(curr->length);
+			ring->slot[j].flags = slot_flags;
 			bus_dmamap_sync(rxr->rxtag, rxr->rx_buffers[l].map,
 				BUS_DMASYNC_POSTREAD);
 			j = (j == lim) ? 0 : j + 1;
diff --git a/sys/dev/netmap/if_igb_netmap.h b/sys/dev/netmap/if_igb_netmap.h
index bd835634884..e817341cc9f 100644
--- a/sys/dev/netmap/if_igb_netmap.h
+++ b/sys/dev/netmap/if_igb_netmap.h
@@ -263,6 +263,8 @@ igb_netmap_rxsync(struct ifnet *ifp, u_int ring_nr, int do_lock)
 	l = rxr->next_to_check;
 	j = netmap_idx_n2k(kring, l);
 	if (netmap_no_pendintr || force_update) {
+		uint16_t slot_flags = kring->nkr_slot_flags;
+
 		for (n = 0; ; n++) {
 			union e1000_adv_rx_desc *curr = &rxr->rx_base[l];
 			uint32_t staterr = le32toh(curr->wb.upper.status_error);
@@ -270,6 +272,7 @@ igb_netmap_rxsync(struct ifnet *ifp, u_int ring_nr, int do_lock)
 			if ((staterr & E1000_RXD_STAT_DD) == 0)
 				break;
 			ring->slot[j].len = le16toh(curr->wb.upper.length);
+			ring->slot[j].flags = slot_flags;
 			bus_dmamap_sync(rxr->ptag,
 				rxr->rx_buffers[l].pmap, BUS_DMASYNC_POSTREAD);
 			j = (j == lim) ? 0 : j + 1;
diff --git a/sys/dev/netmap/if_lem_netmap.h b/sys/dev/netmap/if_lem_netmap.h
index 9f24580a9e8..d3be70017f8 100644
--- a/sys/dev/netmap/if_lem_netmap.h
+++ b/sys/dev/netmap/if_lem_netmap.h
@@ -253,6 +253,8 @@ lem_netmap_rxsync(struct ifnet *ifp, u_int ring_nr, int do_lock)
 	l = adapter->next_rx_desc_to_check;
 	j = netmap_idx_n2k(kring, l);
 	if (netmap_no_pendintr || force_update) {
+		uint16_t slot_flags = kring->nkr_slot_flags;
+
 		for (n = 0; ; n++) {
 			struct e1000_rx_desc *curr = &adapter->rx_desc_base[l];
 			uint32_t staterr = le32toh(curr->status);
@@ -266,6 +268,7 @@ lem_netmap_rxsync(struct ifnet *ifp, u_int ring_nr, int do_lock)
 				len = 0;
 			}
 			ring->slot[j].len = len;
+			ring->slot[j].flags = slot_flags;
 			bus_dmamap_sync(adapter->rxtag,
 				adapter->rx_buffer_area[l].map,
 				    BUS_DMASYNC_POSTREAD);
diff --git a/sys/dev/netmap/if_re_netmap.h b/sys/dev/netmap/if_re_netmap.h
index bdd57035b7b..1c747b7151b 100644
--- a/sys/dev/netmap/if_re_netmap.h
+++ b/sys/dev/netmap/if_re_netmap.h
@@ -245,6 +245,8 @@ re_netmap_rxsync(struct ifnet *ifp, u_int ring_nr, int do_lock)
 	l = sc->rl_ldata.rl_rx_prodidx; /* next pkt to check */
 	j = netmap_idx_n2k(kring, l); /* the kring index */
 	if (netmap_no_pendintr || force_update) {
+		uint16_t slot_flags = kring->nkr_slot_flags;
+
 		for (n = kring->nr_hwavail; n < lim ; n++) {
 			struct rl_desc *cur_rx = &sc->rl_ldata.rl_rx_list[l];
 			uint32_t rxstat = le32toh(cur_rx->rl_cmdstat);
@@ -256,6 +258,7 @@ re_netmap_rxsync(struct ifnet *ifp, u_int ring_nr, int do_lock)
 			/* XXX subtract crc */
 			total_len = (total_len < 4) ? 0 : total_len - 4;
 			kring->ring->slot[j].len = total_len;
+			kring->ring->slot[j].flags = slot_flags;
 			/*  sync was in re_newbuf() */
 			bus_dmamap_sync(sc->rl_ldata.rl_rx_mtag,
 			    rxd[l].rx_dmamap, BUS_DMASYNC_POSTREAD);
diff --git a/sys/dev/netmap/ixgbe_netmap.h b/sys/dev/netmap/ixgbe_netmap.h
index 4ac7b2ea7fe..55660ec086f 100644
--- a/sys/dev/netmap/ixgbe_netmap.h
+++ b/sys/dev/netmap/ixgbe_netmap.h
@@ -483,6 +483,7 @@ ixgbe_netmap_rxsync(struct ifnet *ifp, u_int ring_nr, int do_lock)
 	 */
 	if (netmap_no_pendintr || force_update) {
 		int crclen = ix_crcstrip ? 0 : 4;
+		uint16_t slot_flags = kring->nkr_slot_flags;
 
 		l = rxr->next_to_check;
 		j = netmap_idx_n2k(kring, l);
@@ -494,6 +495,7 @@ ixgbe_netmap_rxsync(struct ifnet *ifp, u_int ring_nr, int do_lock)
 			if ((staterr & IXGBE_RXD_STAT_DD) == 0)
 				break;
 			ring->slot[j].len = le16toh(curr->wb.upper.length) - crclen;
+			ring->slot[j].flags = slot_flags;
 			bus_dmamap_sync(rxr->ptag,
 			    rxr->rx_buffers[l].pmap, BUS_DMASYNC_POSTREAD);
 			j = (j == lim) ? 0 : j + 1;
diff --git a/sys/dev/netmap/netmap_kern.h b/sys/dev/netmap/netmap_kern.h
index bb0d3faae70..6b3e7ac93ce 100644
--- a/sys/dev/netmap/netmap_kern.h
+++ b/sys/dev/netmap/netmap_kern.h
@@ -119,6 +119,10 @@ struct netmap_adapter;
  * RX rings: the next empty buffer (hwcur + hwavail + hwofs) coincides with
  * 	the next empty buffer as known by the hardware (next_to_check or so).
  * TX rings: hwcur + hwofs coincides with next_to_send
+ *
+ * For received packets, slot->flags is set to nkr_slot_flags
+ * so we can provide a proper initial value (e.g. set NS_FORWARD
+ * when operating in 'transparent' mode).
  */
 struct netmap_kring {
 	struct netmap_ring *ring;
@@ -128,6 +132,7 @@ struct netmap_kring {
 #define NKR_PENDINTR	0x1	// Pending interrupt.
 	u_int nkr_num_slots;
 
+	uint16_t	nkr_slot_flags;	/* initial value for flags */
 	int	nkr_hwofs;	/* offset between NIC and netmap ring */
 	struct netmap_adapter *na;
 	NM_SELINFO_T si;	/* poll/select wait queue */