Re: [PATCH] Input: pwm-beeper - fix: scheduling while atomic

From: Manfred Schlaegl
Date: Tue May 24 2016 - 04:33:13 EST


On 2016-05-20 18:59, Dmitry Torokhov wrote:
> Hi Manfred,
>
> On Wed, May 18, 2016 at 05:16:49PM +0200, Manfred Schlaegl wrote:
>> @@ -133,6 +149,8 @@ static int pwm_beeper_remove(struct platform_device *pdev)
>> {
>> struct pwm_beeper *beeper = platform_get_drvdata(pdev);
>>
>> + cancel_work_sync(&beeper->work);
>> +
>> input_unregister_device(beeper->input);
>
> This is racy, request to play may come in after cancel_work_sync()
> returns but before we unregistered input device. I think you want the
> version below.
>

Hi Dmitry,

yes you are right. Thank you for your feedback.
I also see that point, but I think it would be a simpler change just
to cancel the worker after unregistering the device (to reorder
cancel_work_sync and input_unregister_device).

Patch will follow shortly.

What do you think?

Sincerely,
Manfred