diff --git a/net/irda/irttp.c b/net/irda/irttp.c
index ecf4eb2717cb0c4d75b77aa006c8d15235c7d867..9cb79f95bf63953c9bcdf2b379b4ccbb37089ff5 100644
--- a/net/irda/irttp.c
+++ b/net/irda/irttp.c
@@ -1453,6 +1453,7 @@ struct tsap_cb *irttp_dup(struct tsap_cb *orig, void *instance)
 	}
 	/* Dup */
 	memcpy(new, orig, sizeof(struct tsap_cb));
+	spin_lock_init(&new->lock);
 
 	/* We don't need the old instance any more */
 	spin_unlock_irqrestore(&irttp->tsaps->hb_spinlock, flags);