Re: [PATCH 2/3] firmware: google: Unregister driver_info on failure and exit in gsmi

From: patrick . rudolph
Date: Mon Nov 18 2019 - 02:59:37 EST


On Sat, 2019-11-16 at 14:40 +0100, Greg Kroah-Hartman wrote:
> On Fri, Nov 15, 2019 at 02:48:38PM +0100,
> patrick.rudolph@xxxxxxxxxxxxx wrote:
> > From: Arthur Heymans <arthur@xxxxxxxxxxxx>
> >
> > Fix a bug where the kernel module couldn't be loaded after
> > unloading,
> > as the platform driver wasn't released on exit.
> >
> > Signed-off-by: Arthur Heymans <arthur@xxxxxxxxxxxx>
> > ---
> > drivers/firmware/google/gsmi.c | 6 ++++++
> > 1 file changed, 6 insertions(+)
> >
> > diff --git a/drivers/firmware/google/gsmi.c
> > b/drivers/firmware/google/gsmi.c
> > index edaa4e5d84ad..974c769b75cf 100644
> > --- a/drivers/firmware/google/gsmi.c
> > +++ b/drivers/firmware/google/gsmi.c
> > @@ -1016,6 +1016,9 @@ static __init int gsmi_init(void)
> > dma_pool_destroy(gsmi_dev.dma_pool);
> > platform_device_unregister(gsmi_dev.pdev);
> > pr_info("gsmi: failed to load: %d\n", ret);
> > +#ifdef CONFIG_PM
> > + platform_driver_unregister(&gsmi_driver_info);
> > +#endif
> > return ret;
> > }
> >
> > @@ -1037,6 +1040,9 @@ static void __exit gsmi_exit(void)
> > gsmi_buf_free(gsmi_dev.name_buf);
> > dma_pool_destroy(gsmi_dev.dma_pool);
> > platform_device_unregister(gsmi_dev.pdev);
> > +#ifdef CONFIG_PM
> > + platform_driver_unregister(&gsmi_driver_info);
>
> Why the #ifdef here? Why does PM change things?
>
The driver is only registered if CONFIG_PM is selected, thus it only
needs to be unregistered if CONFIG_PM is selected.

See 8942b2d5094b0 for reference.

Regards,
Patrick

> #ifdefs in .c code is really frowned on.
>
> thanks,
>
> greg k-h