diff --git a/lib/bitratestats/rte_bitrate.h b/lib/bitratestats/rte_bitrate.h
index e494389b95a0..843baaf10900 100644
--- a/lib/bitratestats/rte_bitrate.h
+++ b/lib/bitratestats/rte_bitrate.h
@@ -32,6 +32,7 @@ struct rte_stats_bitrates *rte_stats_bitrate_create(void);
  *
  * @param bitrate_data
  *   Pointer allocated by rte_stats_bitrate_create()
+ *   If NULL then, the function does nothing.
  */
 void rte_stats_bitrate_free(struct rte_stats_bitrates *bitrate_data);
 
diff --git a/lib/compressdev/rte_comp.h b/lib/compressdev/rte_comp.h
index 95306c5d0364..b07434ad39b2 100644
--- a/lib/compressdev/rte_comp.h
+++ b/lib/compressdev/rte_comp.h
@@ -471,6 +471,7 @@ rte_comp_op_bulk_alloc(struct rte_mempool *mempool,
  *
  * @param op
  *   Compress operation
+ *   If NULL then, the function does nothing.
  */
 __rte_experimental
 void
diff --git a/lib/cryptodev/rte_crypto.h b/lib/cryptodev/rte_crypto.h
index a864f5036f3a..326764b0f0c0 100644
--- a/lib/cryptodev/rte_crypto.h
+++ b/lib/cryptodev/rte_crypto.h
@@ -339,6 +339,7 @@ __rte_crypto_op_get_priv_data(struct rte_crypto_op *op, uint32_t size)
  * be returned to the mempool.
  *
  * @param	op	symmetric crypto operation
+ * If NULL then, the function does nothing.
  */
 static inline void
 rte_crypto_op_free(struct rte_crypto_op *op)
diff --git a/lib/eal/include/rte_interrupts.h b/lib/eal/include/rte_interrupts.h
index edbf0faeeffd..3ef8ab4621fb 100644
--- a/lib/eal/include/rte_interrupts.h
+++ b/lib/eal/include/rte_interrupts.h
@@ -243,7 +243,8 @@ rte_intr_instance_alloc(uint32_t flags);
  * resources.
  *
  * @param intr_handle
- *  Interrupt handle address.
+ * Interrupt handle address.
+ * If NULL then, the function does nothing.
  *
  */
 __rte_experimental
@@ -746,6 +747,7 @@ rte_intr_vec_list_index_get(const struct rte_intr_handle *intr_handle,
  *
  * @param intr_handle
  *  pointer to the interrupt handle.
+ *  If NULL then, the function does nothing.
  *
  * @return
  *  - On success, zero
diff --git a/lib/efd/rte_efd.h b/lib/efd/rte_efd.h
index d3d7befd0c90..afba38a78c8a 100644
--- a/lib/efd/rte_efd.h
+++ b/lib/efd/rte_efd.h
@@ -146,6 +146,7 @@ rte_efd_create(const char *name, uint32_t max_num_rules, uint32_t key_len,
  *
  * @param table
  *   Table to free
+ *   If NULL then, the function does nothing.
  */
 void
 rte_efd_free(struct rte_efd_table *table);
diff --git a/lib/eventdev/rte_event_ring.h b/lib/eventdev/rte_event_ring.h
index c0861b0ec2db..85c214a678cd 100644
--- a/lib/eventdev/rte_event_ring.h
+++ b/lib/eventdev/rte_event_ring.h
@@ -233,6 +233,7 @@ rte_event_ring_lookup(const char *name);
  *
  * @param r
  *   Ring to free
+ *   If NULL then, the function does nothing.
  */
 void
 rte_event_ring_free(struct rte_event_ring *r);
diff --git a/lib/fib/rte_fib.h b/lib/fib/rte_fib.h
index e592d3251af1..5df6e34bde70 100644
--- a/lib/fib/rte_fib.h
+++ b/lib/fib/rte_fib.h
@@ -124,6 +124,7 @@ rte_fib_find_existing(const char *name);
  *
  * @param fib
  *   FIB object handle
+ *   If NULL then, the function does nothing.
  * @return
  *   None
  */
diff --git a/lib/fib/rte_fib6.h b/lib/fib/rte_fib6.h
index cb133719e175..4029c8f3ee0d 100644
--- a/lib/fib/rte_fib6.h
+++ b/lib/fib/rte_fib6.h
@@ -115,6 +115,7 @@ rte_fib6_find_existing(const char *name);
  *
  * @param fib
  *   FIB object handle
+ *   If NULL then, the function does nothing.
  * @return
  *   None
  */
diff --git a/lib/member/rte_member.h b/lib/member/rte_member.h
index c0689e233e65..ada3b96e5ec1 100644
--- a/lib/member/rte_member.h
+++ b/lib/member/rte_member.h
@@ -444,6 +444,7 @@ rte_member_add(const struct rte_member_setsum *setsum, const void *key,
  *
  * @param setsum
  *   Pointer to the set summary.
+ *   If NULL then, the function does nothing.
  */
 void
 rte_member_free(struct rte_member_setsum *setsum);
diff --git a/lib/reorder/rte_reorder.h b/lib/reorder/rte_reorder.h
index 9de02403746b..ecf83fb5c578 100644
--- a/lib/reorder/rte_reorder.h
+++ b/lib/reorder/rte_reorder.h
@@ -115,6 +115,7 @@ rte_reorder_reset(struct rte_reorder_buffer *b);
  *
  * @param b
  *   reorder buffer instance
+ *   If NULL then, the function does nothing.
  * @return
  *   None
  */
diff --git a/lib/rib/rte_rib.h b/lib/rib/rte_rib.h
index bebb30f7d7cf..bafd2585ac69 100644
--- a/lib/rib/rte_rib.h
+++ b/lib/rib/rte_rib.h
@@ -265,6 +265,7 @@ rte_rib_find_existing(const char *name);
  *
  * @param rib
  *   RIB object handle
+ *   If NULL then, the function does nothing.
  * @return
  *   None
  */
diff --git a/lib/rib/rte_rib6.h b/lib/rib/rte_rib6.h
index 6f532265c657..a2e179ccb4b9 100644
--- a/lib/rib/rte_rib6.h
+++ b/lib/rib/rte_rib6.h
@@ -320,6 +320,7 @@ rte_rib6_find_existing(const char *name);
  *
  * @param rib
  *   RIB object handle
+ *   If NULL then, the function does nothing.
  * @return
  *   None
  */
diff --git a/lib/sched/rte_sched.h b/lib/sched/rte_sched.h
index 3c625ba1698a..d212ad5774e6 100644
--- a/lib/sched/rte_sched.h
+++ b/lib/sched/rte_sched.h
@@ -330,6 +330,7 @@ rte_sched_port_config(struct rte_sched_port_params *params);
  *
  * @param port
  *   Handle to port scheduler instance
+ *   If NULL then, the function does nothing.
  */
 void
 rte_sched_port_free(struct rte_sched_port *port);
diff --git a/lib/stack/rte_stack.h b/lib/stack/rte_stack.h
index 321f4cec1a10..8c3bd4862711 100644
--- a/lib/stack/rte_stack.h
+++ b/lib/stack/rte_stack.h
@@ -215,6 +215,7 @@ rte_stack_create(const char *name, unsigned int count, int socket_id,
  *
  * @param s
  *   Stack to free
+ *   If NULL then, the function does nothing.
  */
 void
 rte_stack_free(struct rte_stack *s);
diff --git a/lib/telemetry/rte_telemetry.h b/lib/telemetry/rte_telemetry.h
index 7bca8a9a49e2..af95fb4f150b 100644
--- a/lib/telemetry/rte_telemetry.h
+++ b/lib/telemetry/rte_telemetry.h
@@ -289,7 +289,7 @@ rte_tel_data_alloc(void);
  *
  * @param data
  *  Pointer to container.
- *.
+ *  If NULL then, the function does nothing.
  */
 void
 rte_tel_data_free(struct rte_tel_data *data);
