2021-08-02 22:16:12

by Salah Triki

Subject: [PATCH] usb: bluetooth: get lock before calling usb_[disable|enable]_autosuspend()

Based on the documentation of usb_[disable|enable]_autosuspend(), the
caller must hold udev's device lock.

Signed-off-by: Salah Triki <[email protected]>
---
drivers/bluetooth/btusb.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c
index a9855a2dd561..2ceb48164b6d 100644
--- a/drivers/bluetooth/btusb.c
+++ b/drivers/bluetooth/btusb.c
@@ -1939,8 +1939,11 @@ static int btusb_setup_csr(struct hci_dev *hdev)

device_set_wakeup_capable(&data->udev->dev, false);
/* Re-enable autosuspend if this was requested */
- if (enable_autosuspend)
+ if (enable_autosuspend) {
+ usb_lock_device(data->udev);
usb_enable_autosuspend(data->udev);
+ usb_unlock_device(data->udev);
+ }
}
}

--
2.25.1

2021-08-03 05:39:40

by Greg Kroah-Hartman

Subject: Re: [PATCH] usb: bluetooth: get lock before calling usb_[disable|enable]_autosuspend()

On Mon, Aug 02, 2021 at 11:14:29PM +0100, Salah Triki wrote:
> Based on the documentation of usb_[disable|enable]_autosuspend(), the
> caller must hold udev's device lock.
>
> Signed-off-by: Salah Triki <[email protected]>
> ---
> drivers/bluetooth/btusb.c | 5 ++++-
> 1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c
> index a9855a2dd561..2ceb48164b6d 100644
> --- a/drivers/bluetooth/btusb.c
> +++ b/drivers/bluetooth/btusb.c
> @@ -1939,8 +1939,11 @@ static int btusb_setup_csr(struct hci_dev *hdev)
>
> device_set_wakeup_capable(&data->udev->dev, false);
> /* Re-enable autosuspend if this was requested */
> - if (enable_autosuspend)
> + if (enable_autosuspend) {
> + usb_lock_device(data->udev);
> usb_enable_autosuspend(data->udev);
> + usb_unlock_device(data->udev);
> + }
> }
> }
>
> --
> 2.25.1
>

As was pointed out elsewhere, this is not correct.

thanks,

greg k-h