diff --git a/lib/librte_ether/rte_ethdev.c b/lib/librte_ether/rte_ethdev.c
index 8c65d72..446c53a 100644
--- a/lib/librte_ether/rte_ethdev.c
+++ b/lib/librte_ether/rte_ethdev.c
@@ -201,19 +201,33 @@ rte_eth_dev_allocated(const char *name)
 {
 	unsigned i;
 
-	for (i = 0; i < nb_ports; i++) {
-		if (strcmp(rte_eth_devices[i].data->name, name) == 0)
+	for (i = 0; i < RTE_MAX_ETHPORTS; i++) {
+		if (rte_eth_devices[i].attached && strcmp(
+				rte_eth_devices[i].data->name, name) == 0)
 			return &rte_eth_devices[i];
 	}
 	return NULL;
 }
 
+static uint8_t
+rte_eth_dev_allocate_new_port(void)
+{
+	unsigned i;
+
+	for (i = 0; i < RTE_MAX_ETHPORTS; i++)
+		if (!rte_eth_devices[i].attached)
+			return i;
+	return RTE_MAX_ETHPORTS;
+}
+
 struct rte_eth_dev *
 rte_eth_dev_allocate(const char *name)
 {
+	uint8_t port_id;
 	struct rte_eth_dev *eth_dev;
 
-	if (nb_ports == RTE_MAX_ETHPORTS) {
+	port_id = rte_eth_dev_allocate_new_port();
+	if (port_id == RTE_MAX_ETHPORTS) {
 		PMD_DEBUG_TRACE("Reached maximum number of Ethernet ports\n");
 		return NULL;
 	}
@@ -226,10 +240,12 @@ rte_eth_dev_allocate(const char *name)
 		return NULL;
 	}
 
-	eth_dev = &rte_eth_devices[nb_ports];
-	eth_dev->data = &rte_eth_dev_data[nb_ports];
+	eth_dev = &rte_eth_devices[port_id];
+	eth_dev->data = &rte_eth_dev_data[port_id];
 	snprintf(eth_dev->data->name, sizeof(eth_dev->data->name), "%s", name);
-	eth_dev->data->port_id = nb_ports++;
+	eth_dev->data->port_id = port_id;
+	eth_dev->attached = 1;
+	nb_ports++;
 	return eth_dev;
 }
 
@@ -283,6 +299,7 @@ rte_eth_dev_init(struct rte_pci_driver *pci_drv,
 			(unsigned) pci_dev->id.device_id);
 	if (rte_eal_process_type() == RTE_PROC_PRIMARY)
 		rte_free(eth_dev->data->dev_private);
+	eth_dev->attached = 0;
 	nb_ports--;
 	return diag;
 }
@@ -308,10 +325,19 @@ rte_eth_driver_register(struct eth_driver *eth_drv)
 	rte_eal_pci_register(&eth_drv->pci_drv);
 }
 
+static int
+rte_eth_dev_validate_port(uint8_t port_id)
+{
+	if (port_id >= RTE_MAX_ETHPORTS)
+		return 1;
+
+	return !rte_eth_devices[port_id].attached;
+}
+
 int
 rte_eth_dev_socket_id(uint8_t port_id)
 {
-	if (port_id >= nb_ports)
+	if (rte_eth_dev_validate_port(port_id))
 		return -1;
 	return rte_eth_devices[port_id].pci_dev->numa_node;
 }
@@ -369,7 +395,7 @@ rte_eth_dev_rx_queue_start(uint8_t port_id, uint16_t rx_queue_id)
 	 * in a multi-process setup*/
 	PROC_PRIMARY_OR_ERR_RET(-E_RTE_SECONDARY);
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return -EINVAL;
 	}
@@ -395,7 +421,7 @@ rte_eth_dev_rx_queue_stop(uint8_t port_id, uint16_t rx_queue_id)
 	 * in a multi-process setup*/
 	PROC_PRIMARY_OR_ERR_RET(-E_RTE_SECONDARY);
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return -EINVAL;
 	}
@@ -421,7 +447,7 @@ rte_eth_dev_tx_queue_start(uint8_t port_id, uint16_t tx_queue_id)
 	 * in a multi-process setup*/
 	PROC_PRIMARY_OR_ERR_RET(-E_RTE_SECONDARY);
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return -EINVAL;
 	}
@@ -447,7 +473,7 @@ rte_eth_dev_tx_queue_stop(uint8_t port_id, uint16_t tx_queue_id)
 	 * in a multi-process setup*/
 	PROC_PRIMARY_OR_ERR_RET(-E_RTE_SECONDARY);
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return -EINVAL;
 	}
@@ -662,7 +688,7 @@ rte_eth_dev_configure(uint8_t port_id, uint16_t nb_rx_q, uint16_t nb_tx_q,
 	 * in a multi-process setup*/
 	PROC_PRIMARY_OR_ERR_RET(-E_RTE_SECONDARY);
 
-	if (port_id >= nb_ports || port_id >= RTE_MAX_ETHPORTS) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return (-EINVAL);
 	}
@@ -847,7 +873,7 @@ rte_eth_dev_start(uint8_t port_id)
 	 * in a multi-process setup*/
 	PROC_PRIMARY_OR_ERR_RET(-E_RTE_SECONDARY);
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%" PRIu8 "\n", port_id);
 		return (-EINVAL);
 	}
@@ -882,7 +908,7 @@ rte_eth_dev_stop(uint8_t port_id)
 	 * in a multi-process setup*/
 	PROC_PRIMARY_OR_RET();
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%" PRIu8 "\n", port_id);
 		return;
 	}
@@ -910,7 +936,7 @@ rte_eth_dev_set_link_up(uint8_t port_id)
 	 * in a multi-process setup*/
 	PROC_PRIMARY_OR_ERR_RET(-E_RTE_SECONDARY);
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return -EINVAL;
 	}
@@ -929,7 +955,7 @@ rte_eth_dev_set_link_down(uint8_t port_id)
 	 * in a multi-process setup*/
 	PROC_PRIMARY_OR_ERR_RET(-E_RTE_SECONDARY);
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return -EINVAL;
 	}
@@ -948,7 +974,7 @@ rte_eth_dev_close(uint8_t port_id)
 	 * in a multi-process setup*/
 	PROC_PRIMARY_OR_RET();
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return;
 	}
@@ -976,7 +1002,7 @@ rte_eth_rx_queue_setup(uint8_t port_id, uint16_t rx_queue_id,
 	 * in a multi-process setup*/
 	PROC_PRIMARY_OR_ERR_RET(-E_RTE_SECONDARY);
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return (-EINVAL);
 	}
@@ -1049,7 +1075,7 @@ rte_eth_tx_queue_setup(uint8_t port_id, uint16_t tx_queue_id,
 	 * in a multi-process setup*/
 	PROC_PRIMARY_OR_ERR_RET(-E_RTE_SECONDARY);
 
-	if (port_id >= RTE_MAX_ETHPORTS || port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return (-EINVAL);
 	}
@@ -1082,7 +1108,7 @@ rte_eth_promiscuous_enable(uint8_t port_id)
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return;
 	}
@@ -1098,7 +1124,7 @@ rte_eth_promiscuous_disable(uint8_t port_id)
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return;
 	}
@@ -1114,7 +1140,7 @@ rte_eth_promiscuous_get(uint8_t port_id)
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return -1;
 	}
@@ -1128,7 +1154,7 @@ rte_eth_allmulticast_enable(uint8_t port_id)
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return;
 	}
@@ -1144,7 +1170,7 @@ rte_eth_allmulticast_disable(uint8_t port_id)
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return;
 	}
@@ -1160,7 +1186,7 @@ rte_eth_allmulticast_get(uint8_t port_id)
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return -1;
 	}
@@ -1188,7 +1214,7 @@ rte_eth_link_get(uint8_t port_id, struct rte_eth_link *eth_link)
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return;
 	}
@@ -1208,7 +1234,7 @@ rte_eth_link_get_nowait(uint8_t port_id, struct rte_eth_link *eth_link)
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return;
 	}
@@ -1228,7 +1254,7 @@ rte_eth_stats_get(uint8_t port_id, struct rte_eth_stats *stats)
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return;
 	}
@@ -1245,7 +1271,7 @@ rte_eth_stats_reset(uint8_t port_id)
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return;
 	}
@@ -1266,7 +1292,7 @@ rte_eth_xstats_get(uint8_t port_id, struct rte_eth_xstats *xstats,
 	uint64_t val;
 	char *stats_ptr;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return -1;
 	}
@@ -1335,7 +1361,7 @@ rte_eth_xstats_reset(uint8_t port_id)
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return;
 	}
@@ -1357,7 +1383,7 @@ set_queue_stats_mapping(uint8_t port_id, uint16_t queue_id, uint8_t stat_idx,
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return -ENODEV;
 	}
@@ -1392,7 +1418,7 @@ rte_eth_dev_info_get(uint8_t port_id, struct rte_eth_dev_info *dev_info)
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return;
 	}
@@ -1412,7 +1438,7 @@ rte_eth_macaddr_get(uint8_t port_id, struct ether_addr *mac_addr)
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return;
 	}
@@ -1426,7 +1452,7 @@ rte_eth_dev_get_mtu(uint8_t port_id, uint16_t *mtu)
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return (-ENODEV);
 	}
@@ -1442,7 +1468,7 @@ rte_eth_dev_set_mtu(uint8_t port_id, uint16_t mtu)
 	int ret;
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return (-ENODEV);
 	}
@@ -1462,7 +1488,7 @@ rte_eth_dev_vlan_filter(uint8_t port_id, uint16_t vlan_id, int on)
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return (-ENODEV);
 	}
@@ -1487,7 +1513,7 @@ rte_eth_dev_set_vlan_strip_on_queue(uint8_t port_id, uint16_t rx_queue_id, int o
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return (-ENODEV);
 	}
@@ -1509,7 +1535,7 @@ rte_eth_dev_set_vlan_ether_type(uint8_t port_id, uint16_t tpid)
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return (-ENODEV);
 	}
@@ -1529,7 +1555,7 @@ rte_eth_dev_set_vlan_offload(uint8_t port_id, int offload_mask)
 	int mask = 0;
 	int cur, org = 0;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return (-ENODEV);
 	}
@@ -1574,7 +1600,7 @@ rte_eth_dev_get_vlan_offload(uint8_t port_id)
 	struct rte_eth_dev *dev;
 	int ret = 0;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return (-ENODEV);
 	}
@@ -1598,7 +1624,7 @@ rte_eth_dev_set_vlan_pvid(uint8_t port_id, uint16_t pvid, int on)
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return (-ENODEV);
 	}
@@ -1616,7 +1642,7 @@ rte_eth_dev_fdir_add_signature_filter(uint8_t port_id,
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return (-ENODEV);
 	}
@@ -1650,7 +1676,7 @@ rte_eth_dev_fdir_update_signature_filter(uint8_t port_id,
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return (-ENODEV);
 	}
@@ -1684,7 +1710,7 @@ rte_eth_dev_fdir_remove_signature_filter(uint8_t port_id,
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return (-ENODEV);
 	}
@@ -1715,7 +1741,7 @@ rte_eth_dev_fdir_get_infos(uint8_t port_id, struct rte_eth_fdir *fdir)
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return (-ENODEV);
 	}
@@ -1740,7 +1766,7 @@ rte_eth_dev_fdir_add_perfect_filter(uint8_t port_id,
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return (-ENODEV);
 	}
@@ -1780,7 +1806,7 @@ rte_eth_dev_fdir_update_perfect_filter(uint8_t port_id,
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return (-ENODEV);
 	}
@@ -1818,7 +1844,7 @@ rte_eth_dev_fdir_remove_perfect_filter(uint8_t port_id,
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return (-ENODEV);
 	}
@@ -1854,7 +1880,7 @@ rte_eth_dev_fdir_set_masks(uint8_t port_id, struct rte_fdir_masks *fdir_mask)
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return (-ENODEV);
 	}
@@ -1874,7 +1900,7 @@ rte_eth_dev_flow_ctrl_get(uint8_t port_id, struct rte_eth_fc_conf *fc_conf)
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return (-ENODEV);
 	}
@@ -1890,7 +1916,7 @@ rte_eth_dev_flow_ctrl_set(uint8_t port_id, struct rte_eth_fc_conf *fc_conf)
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return (-ENODEV);
 	}
@@ -1910,7 +1936,7 @@ rte_eth_dev_priority_flow_ctrl_set(uint8_t port_id, struct rte_eth_pfc_conf *pfc
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return (-ENODEV);
 	}
@@ -1934,7 +1960,7 @@ rte_eth_dev_rss_reta_update(uint8_t port_id, struct rte_eth_rss_reta *reta_conf)
 	uint16_t max_rxq;
 	uint8_t i,j;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return (-ENODEV);
 	}
@@ -1986,7 +2012,7 @@ rte_eth_dev_rss_reta_query(uint8_t port_id, struct rte_eth_rss_reta *reta_conf)
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return (-ENODEV);
 	}
@@ -2007,7 +2033,7 @@ rte_eth_dev_rss_hash_update(uint8_t port_id, struct rte_eth_rss_conf *rss_conf)
 	struct rte_eth_dev *dev;
 	uint16_t rss_hash_protos;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return (-ENODEV);
 	}
@@ -2029,7 +2055,7 @@ rte_eth_dev_rss_hash_conf_get(uint8_t port_id,
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return (-ENODEV);
 	}
@@ -2044,7 +2070,7 @@ rte_eth_dev_udp_tunnel_add(uint8_t port_id,
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return -ENODEV;
 	}
@@ -2070,7 +2096,7 @@ rte_eth_dev_udp_tunnel_delete(uint8_t port_id,
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return -ENODEV;
 	}
@@ -2095,7 +2121,7 @@ rte_eth_led_on(uint8_t port_id)
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return (-ENODEV);
 	}
@@ -2110,7 +2136,7 @@ rte_eth_led_off(uint8_t port_id)
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return (-ENODEV);
 	}
@@ -2150,7 +2176,7 @@ rte_eth_dev_mac_addr_add(uint8_t port_id, struct ether_addr *addr,
 	int index;
 	uint64_t pool_mask;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return (-ENODEV);
 	}
@@ -2201,7 +2227,7 @@ rte_eth_dev_mac_addr_remove(uint8_t port_id, struct ether_addr *addr)
 	struct rte_eth_dev *dev;
 	int index;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return (-ENODEV);
 	}
@@ -2235,7 +2261,7 @@ rte_eth_dev_set_vf_rxmode(uint8_t port_id,  uint16_t vf,
 	struct rte_eth_dev *dev;
 	struct rte_eth_dev_info dev_info;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("set VF RX mode:Invalid port_id=%d\n",
 				port_id);
 		return (-ENODEV);
@@ -2290,7 +2316,7 @@ rte_eth_dev_uc_hash_table_set(uint8_t port_id, struct ether_addr *addr,
 	int ret;
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("unicast hash setting:Invalid port_id=%d\n",
 			port_id);
 		return (-ENODEV);
@@ -2343,7 +2369,7 @@ rte_eth_dev_uc_all_hash_table_set(uint8_t port_id, uint8_t on)
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("unicast hash setting:Invalid port_id=%d\n",
 			port_id);
 		return (-ENODEV);
@@ -2362,7 +2388,7 @@ rte_eth_dev_set_vf_rx(uint8_t port_id,uint16_t vf, uint8_t on)
 	struct rte_eth_dev *dev;
 	struct rte_eth_dev_info dev_info;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return (-ENODEV);
 	}
@@ -2388,7 +2414,7 @@ rte_eth_dev_set_vf_tx(uint8_t port_id,uint16_t vf, uint8_t on)
 	struct rte_eth_dev *dev;
 	struct rte_eth_dev_info dev_info;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("set pool tx:Invalid port_id=%d\n", port_id);
 		return (-ENODEV);
 	}
@@ -2413,7 +2439,7 @@ rte_eth_dev_set_vf_vlan_filter(uint8_t port_id, uint16_t vlan_id,
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("VF VLAN filter:invalid port id=%d\n",
 				port_id);
 		return (-ENODEV);
@@ -2444,7 +2470,7 @@ int rte_eth_set_queue_rate_limit(uint8_t port_id, uint16_t queue_idx,
 	struct rte_eth_dev_info dev_info;
 	struct rte_eth_link link;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("set queue rate limit:invalid port id=%d\n",
 				port_id);
 		return -ENODEV;
@@ -2481,7 +2507,7 @@ int rte_eth_set_vf_rate_limit(uint8_t port_id, uint16_t vf, uint16_t tx_rate,
 	if (q_msk == 0)
 		return 0;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("set VF rate limit:invalid port id=%d\n",
 				port_id);
 		return -ENODEV;
@@ -2515,7 +2541,7 @@ rte_eth_mirror_rule_set(uint8_t port_id,
 {
 	struct rte_eth_dev *dev = &rte_eth_devices[port_id];
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return (-ENODEV);
 	}
@@ -2556,7 +2582,7 @@ rte_eth_mirror_rule_reset(uint8_t port_id, uint8_t rule_id)
 {
 	struct rte_eth_dev *dev = &rte_eth_devices[port_id];
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return (-ENODEV);
 	}
@@ -2581,7 +2607,7 @@ rte_eth_rx_burst(uint8_t port_id, uint16_t queue_id,
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return 0;
 	}
@@ -2601,7 +2627,7 @@ rte_eth_tx_burst(uint8_t port_id, uint16_t queue_id,
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return 0;
 	}
@@ -2621,7 +2647,7 @@ rte_eth_rx_queue_count(uint8_t port_id, uint16_t queue_id)
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return 0;
 	}
@@ -2635,7 +2661,7 @@ rte_eth_rx_descriptor_done(uint8_t port_id, uint16_t queue_id, uint16_t offset)
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return (-ENODEV);
 	}
@@ -2656,7 +2682,7 @@ rte_eth_dev_callback_register(uint8_t port_id,
 
 	if (!cb_fn)
 		return (-EINVAL);
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return (-EINVAL);
 	}
@@ -2696,7 +2722,7 @@ rte_eth_dev_callback_unregister(uint8_t port_id,
 
 	if (!cb_fn)
 		return (-EINVAL);
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return (-EINVAL);
 	}
@@ -2756,7 +2782,7 @@ int rte_eth_dev_bypass_init(uint8_t port_id)
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return (-ENODEV);
 	}
@@ -2776,7 +2802,7 @@ rte_eth_dev_bypass_state_show(uint8_t port_id, uint32_t *state)
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return (-ENODEV);
 	}
@@ -2795,7 +2821,7 @@ rte_eth_dev_bypass_state_set(uint8_t port_id, uint32_t *new_state)
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return (-ENODEV);
 	}
@@ -2815,7 +2841,7 @@ rte_eth_dev_bypass_event_show(uint8_t port_id, uint32_t event, uint32_t *state)
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return (-ENODEV);
 	}
@@ -2835,7 +2861,7 @@ rte_eth_dev_bypass_event_store(uint8_t port_id, uint32_t event, uint32_t state)
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return (-ENODEV);
 	}
@@ -2855,7 +2881,7 @@ rte_eth_dev_wd_timeout_store(uint8_t port_id, uint32_t timeout)
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return (-ENODEV);
 	}
@@ -2875,7 +2901,7 @@ rte_eth_dev_bypass_ver_show(uint8_t port_id, uint32_t *ver)
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return (-ENODEV);
 	}
@@ -2895,7 +2921,7 @@ rte_eth_dev_bypass_wd_timeout_show(uint8_t port_id, uint32_t *wd_timeout)
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return (-ENODEV);
 	}
@@ -2915,7 +2941,7 @@ rte_eth_dev_bypass_wd_reset(uint8_t port_id)
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return (-ENODEV);
 	}
@@ -2937,7 +2963,7 @@ rte_eth_dev_add_syn_filter(uint8_t port_id,
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return -ENODEV;
 	}
@@ -2952,7 +2978,7 @@ rte_eth_dev_remove_syn_filter(uint8_t port_id)
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return -ENODEV;
 	}
@@ -2971,7 +2997,7 @@ rte_eth_dev_get_syn_filter(uint8_t port_id,
 	if (filter == NULL || rx_queue == NULL)
 		return -EINVAL;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return -ENODEV;
 	}
@@ -2987,7 +3013,7 @@ rte_eth_dev_add_ethertype_filter(uint8_t port_id, uint16_t index,
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return -ENODEV;
 	}
@@ -3008,7 +3034,7 @@ rte_eth_dev_remove_ethertype_filter(uint8_t port_id,  uint16_t index)
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return -ENODEV;
 	}
@@ -3027,7 +3053,7 @@ rte_eth_dev_get_ethertype_filter(uint8_t port_id, uint16_t index,
 	if (filter == NULL || rx_queue == NULL)
 		return -EINVAL;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return -ENODEV;
 	}
@@ -3044,7 +3070,7 @@ rte_eth_dev_add_2tuple_filter(uint8_t port_id, uint16_t index,
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return -ENODEV;
 	}
@@ -3066,7 +3092,7 @@ rte_eth_dev_remove_2tuple_filter(uint8_t port_id, uint16_t index)
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return -ENODEV;
 	}
@@ -3085,7 +3111,7 @@ rte_eth_dev_get_2tuple_filter(uint8_t port_id, uint16_t index,
 	if (filter == NULL || rx_queue == NULL)
 		return -EINVAL;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return -ENODEV;
 	}
@@ -3101,7 +3127,7 @@ rte_eth_dev_add_5tuple_filter(uint8_t port_id, uint16_t index,
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return -ENODEV;
 	}
@@ -3124,7 +3150,7 @@ rte_eth_dev_remove_5tuple_filter(uint8_t port_id, uint16_t index)
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return -ENODEV;
 	}
@@ -3143,7 +3169,7 @@ rte_eth_dev_get_5tuple_filter(uint8_t port_id, uint16_t index,
 	if (filter == NULL || rx_queue == NULL)
 		return -EINVAL;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return -ENODEV;
 	}
@@ -3160,7 +3186,7 @@ rte_eth_dev_add_flex_filter(uint8_t port_id, uint16_t index,
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return -ENODEV;
 	}
@@ -3175,7 +3201,7 @@ rte_eth_dev_remove_flex_filter(uint8_t port_id, uint16_t index)
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return -ENODEV;
 	}
@@ -3194,7 +3220,7 @@ rte_eth_dev_get_flex_filter(uint8_t port_id, uint16_t index,
 	if (filter == NULL || rx_queue == NULL)
 		return -EINVAL;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return -ENODEV;
 	}
@@ -3210,7 +3236,7 @@ rte_eth_dev_filter_supported(uint8_t port_id, enum rte_filter_type filter_type)
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return -ENODEV;
 	}
@@ -3227,7 +3253,7 @@ rte_eth_dev_filter_ctrl(uint8_t port_id, enum rte_filter_type filter_type,
 {
 	struct rte_eth_dev *dev;
 
-	if (port_id >= nb_ports) {
+	if (rte_eth_dev_validate_port(port_id)) {
 		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
 		return -ENODEV;
 	}
diff --git a/lib/librte_ether/rte_ethdev.h b/lib/librte_ether/rte_ethdev.h
index c29525b..2cd1c43 100644
--- a/lib/librte_ether/rte_ethdev.h
+++ b/lib/librte_ether/rte_ethdev.h
@@ -1554,6 +1554,7 @@ struct eth_dev_ops {
  * process, while the actual configuration data for the device is shared.
  */
 struct rte_eth_dev {
+	uint8_t attached; /**< Flag indicating the port is attached */
 	eth_rx_burst_t rx_pkt_burst; /**< Pointer to PMD receive function. */
 	eth_tx_burst_t tx_pkt_burst; /**< Pointer to PMD transmit function. */
 	struct rte_eth_dev_data *data;  /**< Pointer to device data */
@@ -1626,6 +1627,10 @@ extern struct rte_eth_dev rte_eth_devices[];
  * initialized by the [matching] Ethernet driver during the PCI probing phase.
  * All devices whose port identifier is in the range
  * [0,  rte_eth_dev_count() - 1] can be operated on by network applications.
+ * immediately after invoking rte_eal_init().
+ * If the application unplugs a port using hotplug function, The enabled port
+ * numbers may be noncontiguous. In the case, the applications need to manage
+ * enabled port by themselves.
  *
  * @return
  *   - The total number of usable Ethernet devices.
