Re: [PATCH v2] Bluetooth: Shutdown controller after workqueues are flushed or cancelled
From: Mattijs Korpershoek
Date: Mon Aug 09 2021 - 05:19:56 EST
Hi Kai-Heng,
Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx> writes:
> Hi Mattijs,
>
>> [snipped]
>
> Thanks for your testing. I think I finally got it:
> btmtksdio_shutdown()
> -> mtk_hci_wmt_sync()
> -> __hci_cmd_send()
> then waiting for BTMTKSDIO_TX_WAIT_VND_EVT, which is cleared in
> btmtksdio_recv_event():
> btmtksdio_recv_event()
> -> hci_recv_frame()
> -> queue_work(hdev->workqueue, &hdev->rx_work);
>
> That means it has to be done before the following drain_workqueue() call.
> Can you please see if moving the ->shutdown() part right before
> drain_workqueue() can fix the issue?
I've tested the following patch:
diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
index 2560ed2f144d..131e69a9a66a 100644
--- a/net/bluetooth/hci_core.c
+++ b/net/bluetooth/hci_core.c
@@ -1757,6 +1757,14 @@ int hci_dev_do_close(struct hci_dev *hdev)
cancel_delayed_work_sync(&adv_instance->rpa_expired_cb);
}
+ if (!hci_dev_test_flag(hdev, HCI_UNREGISTER) &&
+ !hci_dev_test_flag(hdev, HCI_USER_CHANNEL) &&
+ test_bit(HCI_UP, &hdev->flags)) {
+ /* Execute vendor specific shutdown routine */
+ if (hdev->shutdown)
+ hdev->shutdown(hdev);
+ }
+
/* Avoid potential lockdep warnings from the *_flush() calls by
* ensuring the workqueue is empty up front.
*/
@@ -1798,14 +1806,6 @@ int hci_dev_do_close(struct hci_dev *hdev)
clear_bit(HCI_INIT, &hdev->flags);
}
- if (!hci_dev_test_flag(hdev, HCI_UNREGISTER) &&
- !hci_dev_test_flag(hdev, HCI_USER_CHANNEL) &&
- test_bit(HCI_UP, &hdev->flags)) {
- /* Execute vendor specific shutdown routine */
- if (hdev->shutdown)
- hdev->shutdown(hdev);
- }
-
/* flush cmd work */
flush_work(&hdev->cmd_work);
It does not seem to fix the issue.
Adding the bits in btmtksdio_flush() does not change the result of the
above patch.
Here are the logs. These are just with the above patch (not with the
btmtksdio_flush() changes.
dmesg: https://pastebin.com/FZZBkqGC
btmtksdio_ftrace: https://pastebin.com/JQ0UWenY
Mattijs
>
> Kai-Heng
>
>>
>> Mattijs
>>
>> >
>> > Kai-Heng