diff --git a/examples/vhost/main.c b/examples/vhost/main.c
index 85ee8b8..4fd164d 100644
--- a/examples/vhost/main.c
+++ b/examples/vhost/main.c
@@ -3607,9 +3607,14 @@ MAIN(int argc, char *argv[])
 		char pool_name[RTE_MEMPOOL_NAMESIZE];
 		char ring_name[RTE_MEMPOOL_NAMESIZE];
 
-		rx_conf_default.start_rx_per_q = (uint8_t)zero_copy;
+		/*
+		 * Zero copy defers queue RX/TX start to the time when guest
+		 * finishes its startup and packet buffers from that guest are
+		 * available.
+		 */
+		rx_conf_default.rx_deferred_start = (uint8_t)zero_copy;
 		rx_conf_default.rx_drop_en = 0;
-		tx_conf_default.start_tx_per_q = (uint8_t)zero_copy;
+		tx_conf_default.tx_deferred_start = (uint8_t)zero_copy;
 		nb_mbuf = num_rx_descriptor
 			+ num_switching_cores * MBUF_CACHE_SIZE_ZCP
 			+ num_switching_cores * MAX_PKT_BURST;
diff --git a/lib/librte_ether/rte_ethdev.h b/lib/librte_ether/rte_ethdev.h
index 60b24c5..bef8962 100644
--- a/lib/librte_ether/rte_ethdev.h
+++ b/lib/librte_ether/rte_ethdev.h
@@ -604,7 +604,7 @@ struct rte_eth_rxconf {
 	struct rte_eth_thresh rx_thresh; /**< RX ring threshold registers. */
 	uint16_t rx_free_thresh; /**< Drives the freeing of RX descriptors. */
 	uint8_t rx_drop_en; /**< Drop packets if no descriptors are available. */
-	uint8_t start_rx_per_q; /**< start rx per queue. */
+	uint8_t rx_deferred_start; /**< RX not start in rte_eth_dev_start(). */
 };
 
 #define ETH_TXQ_FLAGS_NOMULTSEGS 0x0001 /**< nb_segs=1 for all mbufs */
@@ -625,7 +625,7 @@ struct rte_eth_txconf {
 	uint16_t tx_rs_thresh; /**< Drives the setting of RS bit on TXDs. */
 	uint16_t tx_free_thresh; /**< Drives the freeing of TX buffers. */
 	uint32_t txq_flags; /**< Set flags for the Tx queue */
-	uint8_t start_tx_per_q; /**< start tx per queue. */
+	uint8_t tx_deferred_start; /**< TX not start in rte_eth_dev_start(). */
 };
 
 /**
@@ -1795,7 +1795,9 @@ extern int rte_eth_tx_queue_setup(uint8_t port_id, uint16_t tx_queue_id,
 extern int rte_eth_dev_socket_id(uint8_t port_id);
 
 /*
- * Start specified RX queue of a port
+ * Allocate mbuf from mempool, setup the DMA physical address
+ * and then start RX for specified queue of a port. It is used
+ * when rx_deferred_start flag of the specified queue is true.
  *
  * @param port_id
  *   The port identifier of the Ethernet device
@@ -1827,7 +1829,8 @@ extern int rte_eth_dev_rx_queue_start(uint8_t port_id, uint16_t rx_queue_id);
 extern int rte_eth_dev_rx_queue_stop(uint8_t port_id, uint16_t rx_queue_id);
 
 /*
- * Start specified TX queue of a port
+ * Start TX for specified queue of a port. It is used when tx_deferred_start
+ * flag of the specified queue is true.
  *
  * @param port_id
  *   The port identifier of the Ethernet device
diff --git a/lib/librte_pmd_i40e/i40e_ethdev.c b/lib/librte_pmd_i40e/i40e_ethdev.c
index a00d6ca..26f1799 100644
--- a/lib/librte_pmd_i40e/i40e_ethdev.c
+++ b/lib/librte_pmd_i40e/i40e_ethdev.c
@@ -3017,7 +3017,7 @@ i40e_vsi_switch_tx_queues(struct i40e_vsi *vsi, bool on)
 		txq = dev_data->tx_queues[i];
 		/* Don't operate the queue if not configured or
 		 * if starting only per queue */
-		if (!txq->q_set || (on && txq->start_tx_per_q))
+		if (!txq->q_set || (on && txq->tx_deferred_start))
 			continue;
 		if (on)
 			ret = i40e_dev_tx_queue_start(dev, i);
@@ -3095,7 +3095,7 @@ i40e_vsi_switch_rx_queues(struct i40e_vsi *vsi, bool on)
 		rxq = dev_data->rx_queues[i];
 		/* Don't operate the queue if not configured or
 		 * if starting only per queue */
-		if (!rxq->q_set || (on && rxq->start_rx_per_q))
+		if (!rxq->q_set || (on && rxq->rx_deferred_start))
 			continue;
 		if (on)
 			ret = i40e_dev_rx_queue_start(dev, i);
diff --git a/lib/librte_pmd_i40e/i40e_ethdev_vf.c b/lib/librte_pmd_i40e/i40e_ethdev_vf.c
index f6c4873..809c1f0 100644
--- a/lib/librte_pmd_i40e/i40e_ethdev_vf.c
+++ b/lib/librte_pmd_i40e/i40e_ethdev_vf.c
@@ -675,7 +675,7 @@ i40evf_start_queues(struct rte_eth_dev *dev)
 
 	for (i = 0; i < dev->data->nb_rx_queues; i++) {
 		rxq = dev_data->rx_queues[i];
-		if (rxq->start_rx_per_q)
+		if (rxq->rx_deferred_start)
 			continue;
 		if (i40evf_dev_rx_queue_start(dev, i) != 0) {
 			PMD_DRV_LOG(ERR, "Fail to start queue %u", i);
@@ -685,7 +685,7 @@ i40evf_start_queues(struct rte_eth_dev *dev)
 
 	for (i = 0; i < dev->data->nb_tx_queues; i++) {
 		txq = dev_data->tx_queues[i];
-		if (txq->start_tx_per_q)
+		if (txq->tx_deferred_start)
 			continue;
 		if (i40evf_dev_tx_queue_start(dev, i) != 0) {
 			PMD_DRV_LOG(ERR, "Fail to start queue %u", i);
diff --git a/lib/librte_pmd_i40e/i40e_rxtx.c b/lib/librte_pmd_i40e/i40e_rxtx.c
index 099699c..7c5b6a8 100644
--- a/lib/librte_pmd_i40e/i40e_rxtx.c
+++ b/lib/librte_pmd_i40e/i40e_rxtx.c
@@ -1609,7 +1609,7 @@ i40e_dev_rx_queue_setup(struct rte_eth_dev *dev,
 							0 : ETHER_CRC_LEN);
 	rxq->drop_en = rx_conf->rx_drop_en;
 	rxq->vsi = vsi;
-	rxq->start_rx_per_q = rx_conf->start_rx_per_q;
+	rxq->rx_deferred_start = rx_conf->rx_deferred_start;
 
 	/* Allocate the maximun number of RX ring hardware descriptor. */
 	ring_size = sizeof(union i40e_rx_desc) * I40E_MAX_RING_DESC;
@@ -1895,7 +1895,7 @@ i40e_dev_tx_queue_setup(struct rte_eth_dev *dev,
 	txq->port_id = dev->data->port_id;
 	txq->txq_flags = tx_conf->txq_flags;
 	txq->vsi = vsi;
-	txq->start_tx_per_q = tx_conf->start_tx_per_q;
+	txq->tx_deferred_start = tx_conf->tx_deferred_start;
 
 #ifdef RTE_LIBRTE_XEN_DOM0
 	txq->tx_ring_phys_addr = rte_mem_phy2mch(tz->memseg_id, tz->phys_addr);
diff --git a/lib/librte_pmd_i40e/i40e_rxtx.h b/lib/librte_pmd_i40e/i40e_rxtx.h
index 4478592..af932e3 100644
--- a/lib/librte_pmd_i40e/i40e_rxtx.h
+++ b/lib/librte_pmd_i40e/i40e_rxtx.h
@@ -112,7 +112,7 @@ struct i40e_rx_queue {
 	uint16_t max_pkt_len; /* Maximum packet length */
 	uint8_t hs_mode; /* Header Split mode */
 	bool q_set; /**< indicate if rx queue has been configured */
-	bool start_rx_per_q; /**< don't start this queue in dev start */
+	bool rx_deferred_start; /**< don't start this queue in dev start */
 };
 
 struct i40e_tx_entry {
@@ -151,7 +151,7 @@ struct i40e_tx_queue {
 	uint16_t tx_next_dd;
 	uint16_t tx_next_rs;
 	bool q_set; /**< indicate if tx queue has been configured */
-	bool start_tx_per_q; /**< don't start this queue in dev start */
+	bool tx_deferred_start; /**< don't start this queue in dev start */
 };
 
 int i40e_dev_rx_queue_start(struct rte_eth_dev *dev, uint16_t rx_queue_id);
diff --git a/lib/librte_pmd_ixgbe/ixgbe_rxtx.c b/lib/librte_pmd_ixgbe/ixgbe_rxtx.c
index 52ec99e..d436151 100644
--- a/lib/librte_pmd_ixgbe/ixgbe_rxtx.c
+++ b/lib/librte_pmd_ixgbe/ixgbe_rxtx.c
@@ -1851,7 +1851,7 @@ ixgbe_dev_tx_queue_setup(struct rte_eth_dev *dev,
 	txq->port_id = dev->data->port_id;
 	txq->txq_flags = tx_conf->txq_flags;
 	txq->ops = &def_txq_ops;
-	txq->start_tx_per_q = tx_conf->start_tx_per_q;
+	txq->tx_deferred_start = tx_conf->tx_deferred_start;
 
 	/*
 	 * Modification to set VFTDT for virtual function if vf is detected
@@ -2121,7 +2121,7 @@ ixgbe_dev_rx_queue_setup(struct rte_eth_dev *dev,
 	rxq->crc_len = (uint8_t) ((dev->data->dev_conf.rxmode.hw_strip_crc) ?
 							0 : ETHER_CRC_LEN);
 	rxq->drop_en = rx_conf->rx_drop_en;
-	rxq->start_rx_per_q = rx_conf->start_rx_per_q;
+	rxq->rx_deferred_start = rx_conf->rx_deferred_start;
 
 	/*
 	 * Allocate RX ring hardware descriptors. A memzone large enough to
@@ -3693,13 +3693,13 @@ ixgbe_dev_rxtx_start(struct rte_eth_dev *dev)
 
 	for (i = 0; i < dev->data->nb_tx_queues; i++) {
 		txq = dev->data->tx_queues[i];
-		if (!txq->start_tx_per_q)
+		if (!txq->tx_deferred_start)
 			ixgbe_dev_tx_queue_start(dev, i);
 	}
 
 	for (i = 0; i < dev->data->nb_rx_queues; i++) {
 		rxq = dev->data->rx_queues[i];
-		if (!rxq->start_rx_per_q)
+		if (!rxq->rx_deferred_start)
 			ixgbe_dev_rx_queue_start(dev, i);
 	}
 
diff --git a/lib/librte_pmd_ixgbe/ixgbe_rxtx.h b/lib/librte_pmd_ixgbe/ixgbe_rxtx.h
index 7b5ac0e..228ee02 100644
--- a/lib/librte_pmd_ixgbe/ixgbe_rxtx.h
+++ b/lib/librte_pmd_ixgbe/ixgbe_rxtx.h
@@ -126,7 +126,8 @@ struct igb_rx_queue {
 	uint8_t             port_id;  /**< Device port identifier. */
 	uint8_t             crc_len;  /**< 0 if CRC stripped, 4 otherwise. */
 	uint8_t             drop_en;  /**< If not 0, set SRRCTL.Drop_En. */
-	uint8_t             start_rx_per_q;
+	uint8_t             rx_deferred_start;
+			    /**< don't start this queue in dev start. */
 #ifdef RTE_LIBRTE_IXGBE_RX_ALLOW_BULK_ALLOC
 	/** need to alloc dummy mbuf, for wraparound when scanning hw ring */
 	struct rte_mbuf fake_mbuf;
@@ -207,7 +208,8 @@ struct igb_tx_queue {
 	/** Hardware context0 history. */
 	struct ixgbe_advctx_info ctx_cache[IXGBE_CTX_NUM];
 	struct ixgbe_txq_ops *ops;          /**< txq ops */
-	uint8_t             start_tx_per_q;
+	uint8_t             tx_deferred_start;
+			    /**< don't start this queue in dev start. */
 };
 
 struct ixgbe_txq_ops {
