On Wed, Jul 27, 2022 at 07:00:00AM +0900, Tetsuo Handa wrote:
> syzbot is reporting hung task at __input_unregister_device() [1], for
> iforce_close() waiting at wait_event_interruptible() with dev->mutex held
> is blocking input_disconnect_device() from __input_unregister_device().
>
> It seems that the cause is simply that commit c2b27ef672992a20 ("Input:
> iforce - wait for command completion when closing the device") forgot to
> call wake_up() after clear_bit().
>
> Fix this problem by introducing a helper that calls clear_bit() followed
> by wake_up_all().
>
> Link: https://syzkaller.appspot.com/bug?extid=deb6abc36aad4008f407 [1]
> Reported-by: syzbot <syzbot+deb6abc36aad4008f407@xxxxxxxxxxxxxxxxxxxxxxxxx>
> Fixes: c2b27ef672992a20 ("Input: iforce - wait for command completion when closing the device")
> Tested-by: syzbot <syzbot+deb6abc36aad4008f407@xxxxxxxxxxxxxxxxxxxxxxxxx>
> Suggested-by: Fabio M. De Francesco <fmdefrancesco@xxxxxxxxx>
> Co-developed-by: Hillf Danton <hdanton@xxxxxxxx>
> Signed-off-by: Hillf Danton <hdanton@xxxxxxxx>
> Signed-off-by: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx>
Applied, thank you.
--
Dmitry
