diff --git a/lib/iscsi/iscsi_subsystem.c b/lib/iscsi/iscsi_subsystem.c
index 4b77dae84..528e48fd3 100644
--- a/lib/iscsi/iscsi_subsystem.c
+++ b/lib/iscsi/iscsi_subsystem.c
@@ -294,13 +294,9 @@ void spdk_put_pdu(struct spdk_iscsi_pdu *pdu)
 		return;
 	}
 
+	assert(pdu->ref > 0);
 	pdu->ref--;
 
-	if (pdu->ref < 0) {
-		SPDK_ERRLOG("Negative PDU refcount: %p\n", pdu);
-		pdu->ref = 0;
-	}
-
 	if (pdu->ref == 0) {
 		if (pdu->mobj) {
 			spdk_mempool_put(pdu->mobj->mp, (void *)pdu->mobj);