--- y/net/bluetooth/hci_core.c
+++ x/net/bluetooth/hci_core.c
@@ -2675,6 +2675,7 @@ void hci_unregister_dev(struct hci_dev *
 	list_del(&hdev->list);
 	write_unlock(&hci_dev_list_lock);
 
+	cancel_work_sync(&hdev->power_on);
 	hci_cmd_sync_clear(hdev);
 
 	if (!test_bit(HCI_QUIRK_NO_SUSPEND_NOTIFIER, &hdev->quirks))
--- y/net/bluetooth/hci_sync.c
+++ x/net/bluetooth/hci_sync.c
@@ -4049,6 +4049,7 @@ setup_failed:
 			hdev->flush(hdev);
 
 		if (hdev->sent_cmd) {
+			cancel_delayed_work_sync(&hdev->cmd_timer);
 			kfree_skb(hdev->sent_cmd);
 			hdev->sent_cmd = NULL;
 		}
@@ -4088,7 +4089,6 @@ int hci_dev_close_sync(struct hci_dev *h
 
 	bt_dev_dbg(hdev, "");
 
-	cancel_work_sync(&hdev->power_on);
 	cancel_delayed_work(&hdev->power_off);
 	cancel_delayed_work(&hdev->ncmd_timer);