Re: [PATCH] fujitsu-laptop: driver [un]registration fixes

Jonathan Woithe
2009-12-21T22:32:48Z

Hi Dmitry

> On Wed, Jul 29, 2009 at 10:15:33PM +0200, Bartlomiej Zolnierkiewicz wrote:
> > @@ -722,22 +722,22 @@ static int acpi_fujitsu_add(struct acpi_
> >
> > return result;
> >
> > -end:
> > +err_unregister_input_dev:
> > + input_unregister_device(input);
> > err_free_input_dev:
> > input_free_device(input);
> > err_stop:
>
> Just noticed it scanning ACPI list. You must not use input_free_device()
> after calling input_unregister_device() since unregister likely drops the
> last reference to the device and it will get freed by input core.

So what's the correct way to deal with that in this case? Something like

-end:
+err_unregister_input_dev:
+ input_unregister_device(input);
+ goto err_stop;
err_free_input_dev:
input_free_device(input);
err_stop:

(with a short comment to explain the goto) would circumvent the problem but
it looks ugly (at least to my eyes - I've never really liked "goto"s :-) ).

> For polled input devices you need to use both unregister and free though
> because polled device structure is not refcounted (but underlying input
> device is).

This isn't a polled input device AFAIK so this doesn't apply here, right?

Regards
jonathan