diff --git a/drivers/infiniband/core/cm.c b/drivers/infiniband/core/cm.c
index 07fb8d3c037f..d45e3909dafe 100644
--- a/drivers/infiniband/core/cm.c
+++ b/drivers/infiniband/core/cm.c
@@ -166,7 +166,7 @@ struct cm_port {
 struct cm_device {
 	struct kref kref;
 	struct list_head list;
-	spinlock_t mad_agent_lock;
+	rwlock_t mad_agent_lock;
 	struct ib_device *ib_device;
 	u8 ack_delay;
 	int going_down;
@@ -284,7 +284,7 @@ static struct ib_mad_send_buf *cm_alloc_msg(struct cm_id_private *cm_id_priv)
 	if (!cm_id_priv->av.port)
 		return ERR_PTR(-EINVAL);
 
-	spin_lock(&cm_id_priv->av.port->cm_dev->mad_agent_lock);
+	read_lock(&cm_id_priv->av.port->cm_dev->mad_agent_lock);
 	mad_agent = cm_id_priv->av.port->mad_agent;
 	if (!mad_agent) {
 		m = ERR_PTR(-EINVAL);
@@ -315,7 +315,7 @@ static struct ib_mad_send_buf *cm_alloc_msg(struct cm_id_private *cm_id_priv)
 	m->context[0] = cm_id_priv;
 
 out:
-	spin_unlock(&cm_id_priv->av.port->cm_dev->mad_agent_lock);
+	read_unlock(&cm_id_priv->av.port->cm_dev->mad_agent_lock);
 	return m;
 }
 
@@ -1294,10 +1294,10 @@ static __be64 cm_form_tid(struct cm_id_private *cm_id_priv)
 	if (!cm_id_priv->av.port)
 		return cpu_to_be64(low_tid);
 
-	spin_lock(&cm_id_priv->av.port->cm_dev->mad_agent_lock);
+	read_lock(&cm_id_priv->av.port->cm_dev->mad_agent_lock);
 	if (cm_id_priv->av.port->mad_agent)
 		hi_tid = ((u64)cm_id_priv->av.port->mad_agent->hi_tid) << 32;
-	spin_unlock(&cm_id_priv->av.port->cm_dev->mad_agent_lock);
+	read_unlock(&cm_id_priv->av.port->cm_dev->mad_agent_lock);
 	return cpu_to_be64(hi_tid | low_tid);
 }
 
@@ -4374,7 +4374,7 @@ static int cm_add_one(struct ib_device *ib_device)
 		return -ENOMEM;
 
 	kref_init(&cm_dev->kref);
-	spin_lock_init(&cm_dev->mad_agent_lock);
+	rwlock_init(&cm_dev->mad_agent_lock);
 	cm_dev->ib_device = ib_device;
 	cm_dev->ack_delay = ib_device->attrs.local_ca_ack_delay;
 	cm_dev->going_down = 0;
@@ -4490,9 +4490,9 @@ static void cm_remove_one(struct ib_device *ib_device, void *client_data)
 		 * The above ensures no call paths from the work are running,
 		 * the remaining paths all take the mad_agent_lock.
 		 */
-		spin_lock(&cm_dev->mad_agent_lock);
+		write_lock(&cm_dev->mad_agent_lock);
 		port->mad_agent = NULL;
-		spin_unlock(&cm_dev->mad_agent_lock);
+		write_unlock(&cm_dev->mad_agent_lock);
 		ib_unregister_mad_agent(mad_agent);
 		ib_port_unregister_client_groups(ib_device, i,
 						 cm_counter_groups);