diff --git a/kernel/ethosu_cancel_inference.c b/kernel/ethosu_cancel_inference.c
index 6661522..4d7b544 100644
--- a/kernel/ethosu_cancel_inference.c
+++ b/kernel/ethosu_cancel_inference.c
@@ -159,11 +159,12 @@
 	struct ethosu_mailbox_msg *msg;
 	struct ethosu_cancel_inference *cancellation;
 
-	msg = ethosu_mailbox_find(mailbox, msg_id);
+	msg = ethosu_mailbox_find(mailbox, msg_id,
+				  ETHOSU_CORE_MSG_CANCEL_INFERENCE_REQ);
 	if (IS_ERR(msg)) {
 		dev_warn(dev,
-			 "Id for cancel inference msg not found. id=%ddev",
-			 msg_id);
+			 "Id for cancel inference msg not found. Id=0x%x: %ld",
+			 msg_id, PTR_ERR(msg));
 
 		return;
 	}
diff --git a/kernel/ethosu_capabilities.c b/kernel/ethosu_capabilities.c
index 8611edf..83bd8cf 100644
--- a/kernel/ethosu_capabilities.c
+++ b/kernel/ethosu_capabilities.c
@@ -68,11 +68,12 @@
 	struct ethosu_mailbox_msg *msg;
 	struct ethosu_capabilities *cap;
 
-	msg = ethosu_mailbox_find(mailbox, msg_id);
+	msg = ethosu_mailbox_find(mailbox, msg_id,
+				  ETHOSU_CORE_MSG_CAPABILITIES_REQ);
 	if (IS_ERR(msg)) {
 		dev_warn(dev,
-			 "Id for capabilities msg not found. id=%d\n",
-			 msg_id);
+			 "Id for capabilities msg not found. Id=0x%0x: %ld\n",
+			 msg_id, PTR_ERR(msg));
 
 		return;
 	}
diff --git a/kernel/ethosu_inference.c b/kernel/ethosu_inference.c
index 6befd3a..dd0b7b9 100644
--- a/kernel/ethosu_inference.c
+++ b/kernel/ethosu_inference.c
@@ -429,11 +429,12 @@
 	int ret;
 	int i;
 
-	msg = ethosu_mailbox_find(mailbox, msg_id);
+	msg = ethosu_mailbox_find(mailbox, msg_id,
+				  ETHOSU_CORE_MSG_INFERENCE_REQ);
 	if (IS_ERR(msg)) {
 		dev_warn(dev,
-			 "Id for inference msg not found. Id=%d\n",
-			 msg_id);
+			 "Id for inference msg not found. Id=0x%x: %ld\n",
+			 msg_id, PTR_ERR(msg));
 
 		return;
 	}
diff --git a/kernel/ethosu_mailbox.c b/kernel/ethosu_mailbox.c
index 4c64f17..3e7284b 100644
--- a/kernel/ethosu_mailbox.c
+++ b/kernel/ethosu_mailbox.c
@@ -79,12 +79,16 @@
 }
 
 struct ethosu_mailbox_msg *ethosu_mailbox_find(struct ethosu_mailbox *mbox,
-					       int msg_id)
+					       int msg_id,
+					       uint32_t msg_type)
 {
 	struct ethosu_mailbox_msg *ptr = (struct ethosu_mailbox_msg *)idr_find(
 		&mbox->msg_idr, msg_id);
 
 	if (ptr == NULL)
+		return ERR_PTR(-ENOENT);
+
+	if (ptr->type != msg_type)
 		return ERR_PTR(-EINVAL);
 
 	return ptr;
@@ -147,6 +151,8 @@
 		}
 	};
 
+	msg->type = rpmsg.header.type;
+
 	return rpmsg_send(mbox->ept, &rpmsg, sizeof(rpmsg.header));
 }
 
@@ -172,6 +178,8 @@
 	struct ethosu_core_msg_inference_req *inf_req = &rpmsg.inf_req;
 	uint32_t i;
 
+	msg->type = rpmsg.header.type;
+
 	/* Verify that the uapi and core has the same number of pmus */
 	if (pmu_event_config_count != ETHOSU_CORE_PMU_MAX) {
 		dev_err(mbox->dev, "PMU count misconfigured.");
@@ -218,6 +226,8 @@
 	};
 	struct ethosu_core_msg_network_info_req *info_req = &rpmsg.net_info_req;
 
+	msg->type = rpmsg.header.type;
+
 	if (network != NULL) {
 		info_req->network.type = ETHOSU_CORE_NETWORK_BUFFER;
 		ethosu_core_set_size(network, &info_req->network.buffer);
@@ -246,6 +256,8 @@
 		}
 	};
 
+	msg->type = rpmsg.header.type;
+
 	return rpmsg_send(mbox->ept, &rpmsg,
 			  sizeof(rpmsg.header) + sizeof(rpmsg.cancel_req));
 }
diff --git a/kernel/ethosu_mailbox.h b/kernel/ethosu_mailbox.h
index edf922b..c192b54 100644
--- a/kernel/ethosu_mailbox.h
+++ b/kernel/ethosu_mailbox.h
@@ -51,8 +51,9 @@
 };
 
 struct ethosu_mailbox_msg {
-	int  id;
-	void (*fail)(struct ethosu_mailbox_msg *msg);
+	int      id;
+	uint32_t type;
+	void     (*fail)(struct ethosu_mailbox_msg *msg);
 };
 
 /****************************************************************************
@@ -93,7 +94,8 @@
  * Return: a valid pointer on success, otherwise an error ptr.
  */
 struct ethosu_mailbox_msg *ethosu_mailbox_find(struct ethosu_mailbox *mbox,
-					       int msg_id);
+					       int msg_id,
+					       uint32_t msg_type);
 
 /**
  * ethosu_mailbox_fail() - Fail mailbox messages
diff --git a/kernel/ethosu_network_info.c b/kernel/ethosu_network_info.c
index 0e205db..5bfa150 100644
--- a/kernel/ethosu_network_info.c
+++ b/kernel/ethosu_network_info.c
@@ -127,11 +127,12 @@
 	struct ethosu_network_info *info;
 	uint32_t i;
 
-	msg = ethosu_mailbox_find(mailbox, msg_id);
+	msg = ethosu_mailbox_find(mailbox, msg_id,
+				  ETHOSU_CORE_MSG_NETWORK_INFO_REQ);
 	if (IS_ERR(msg)) {
 		dev_warn(dev,
-			 "Id for network info msg not found. msg.id=0x%x\n",
-			 msg_id);
+			 "Id for network info msg not found. Id=0x%x: %ld\n",
+			 msg_id, PTR_ERR(msg));
 
 		return;
 	}