Re: [PATCH v2] Bluetooth: Shutdown controller after workqueues are flushed or cancelled

On Tue, Aug 3, 2021 at 4:21 PM Mattijs Korpershoek
[off-list ref] wrote:

quoted

Hi Kai-Heng,

Kai-Heng Feng [off-list ref] writes:

quoted

Hi Mattijs,

On Fri, Jul 30, 2021 at 7:40 PM Mattijs Korpershoek
[off-list ref] wrote:

quoted

Hi Kai-Heng,

[snipped]

quoted

Thank you for your help. Sorry I did not post the logs previously.

dmesg: https://pastebin.com/tpWDNyQr
ftrace on btmtksdio: https://pastebin.com/jmhvmwUw

Seems like btmtksdio needs shudown() to be called before flush().
Since the order was there for a very long time, changing the calling
order indeed can break what driver expects.
Can you please test the following patch:

diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
index 2560ed2f144d..a61e610a400c 100644
--- a/net/bluetooth/hci_core.c
+++ b/net/bluetooth/hci_core.c

@@ -1785,6 +1785,14 @@ int hci_dev_do_close(struct hci_dev *hdev)
        aosp_do_close(hdev);
        msft_do_close(hdev);

+       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);
+       }
+
        if (hdev->flush)
                hdev->flush(hdev);

@@ -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);

Thanks for the patch and your help.
I've tried it, but it seems that it does not improve for me.
I'm still observing:

i500-pumpkin login: root
root@i500-pumpkin:~# hciconfig hci0 up
Can't init device hci0: Connection timed out (110)

Logs for this session:
dmesg:   https://pastebin.com/iAFk5Tzi
ftrace:  https://pastebin.com/kEMWSYrE

Thanks for the testing!
What about moving the shutdown() part right after hci_req_sync_lock()
so tx/rx can still work:

diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
index 2560ed2f144d4..be3113fb7d4b0 100644
--- a/net/bluetooth/hci_core.c
+++ b/net/bluetooth/hci_core.c

@@ -1727,6 +1727,14 @@ int hci_dev_do_close(struct hci_dev *hdev)
        hci_request_cancel_all(hdev);
        hci_req_sync_lock(hdev);

+       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);
+       }
+
        if (!test_and_clear_bit(HCI_UP, &hdev->flags)) {
                cancel_delayed_work_sync(&hdev->cmd_timer);
                hci_req_sync_unlock(hdev);

@@ -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);