diff --git a/app/test-pmd/csumonly.c b/app/test-pmd/csumonly.c
index 21210aff43..d73f08b2c6 100644
--- a/app/test-pmd/csumonly.c
+++ b/app/test-pmd/csumonly.c
@@ -870,16 +870,28 @@ pkt_burst_checksum_forward(struct fwd_stream *fs)
 
 	/* receive a burst of packet */
 	nb_rx = common_fwd_stream_receive(fs, pkts_burst, nb_pkt_per_burst);
-	if (unlikely(nb_rx == 0))
+	if (unlikely(nb_rx == 0)) {
+#ifndef RTE_LIB_GRO
 		return false;
+#else
+		gro_enable = gro_ports[fs->rx_port].enable;
+		/*
+		 * Check if packets need to be flushed in the GRO context
+		 * due to a timeout.
+		 *
+		 * Continue only in GRO heavyweight mode and if there are
+		 * packets in the GRO context.
+		 */
+		if (!gro_enable || (gro_flush_cycles == GRO_DEFAULT_FLUSH_CYCLES) ||
+			(rte_gro_get_pkt_count(current_fwd_lcore()->gro_ctx) == 0))
+			return false;
+#endif
+	}
 
 	rx_bad_ip_csum = 0;
 	rx_bad_l4_csum = 0;
 	rx_bad_outer_l4_csum = 0;
 	rx_bad_outer_ip_csum = 0;
-#ifdef RTE_LIB_GRO
-	gro_enable = gro_ports[fs->rx_port].enable;
-#endif
 
 	txp = &ports[fs->tx_port];
 	tx_offloads = txp->dev_conf.txmode.offloads;
@@ -1110,6 +1122,7 @@ pkt_burst_checksum_forward(struct fwd_stream *fs)
 	}
 
 #ifdef RTE_LIB_GRO
+	gro_enable = gro_ports[fs->rx_port].enable;
 	if (unlikely(gro_enable)) {
 		if (gro_flush_cycles == GRO_DEFAULT_FLUSH_CYCLES) {
 			nb_rx = rte_gro_reassemble_burst(pkts_burst, nb_rx,