--- zzzz-none-000/linux-4.9.279/drivers/char/hpet.c	2021-08-08 06:38:54.000000000 +0000
+++ puma7-atom-6591-750/linux-4.9.279/drivers/char/hpet.c	2023-02-08 11:43:42.000000000 +0000
@@ -278,8 +278,13 @@
 			}
 
 	if (!devp) {
+		char comm[TASK_COMM_LEN];
+
 		spin_unlock_irq(&hpet_lock);
 		mutex_unlock(&hpet_mutex);
+		pr_warning("hpet: No free device for process %d (comm=%s)\n",
+				task_pid_nr(current),
+				get_task_comm(comm, current));
 		return -EBUSY;
 	}