Re: [PATCH] mcb: Fix incorrect sanity check

Jose Javier Rodriguez Barbarin
2026-01-16T10:30:46Z

On Fri, Nov 21, 2025 at 11:54:08AM +0100, Johannes Thumshirn wrote:
> On 11/21/25 11:33 AM, Jose Javier Rodriguez Barbarin wrote:
> > On Thu, Nov 20, 2025 at 12:48:45PM +0100, Johannes Thumshirn wrote:
> > > On 11/20/25 12:37 PM, Jose Javier Rodriguez Barbarin wrote:
> > > > __mcb_register_driver() makes some sanity checks over mcb_driver
> > > > to check if .probe and .remove callbacks are set. However, not all
> > > > mcb device drivers implement .remove callback.
> > > >
> > > > Remove .remove check to ensure all mcb device drivers can be loaded.
> > > The only driver I can see that doesn't implement a .remove method is
> > > gpio-menz127.c.
> > Yes. In the past gpio-menz127.c also implemented .remove method, however in
> >
> > 3bd13ae04ccc ("gpio: menz127: simplify error path and remove remove()")
> >
> > The driver changed, using now devm_* functions so .remove was no longer necessary.
> >
> > > Is this safe?
> > >
> > From the point of view of mcb bus it should be safe becase I protected the call
> > of .remove on mcb_remove(), preventing possible crashes when the driver is removed
> > from the bus.
> >
> > I'm afraid I'm lossing something because I cannot understand why these changes are or
> > not safe. Could you explain me why you understand that these changes are unsafe?
>
>
> Thanks this is the information I was missing from the changelog. I'll change
> the commit message to:
>
> __mcb_register_driver() makes some sanity checks over mcb_driver
> to check if .probe and .remove callbacks are set. However, since commit
> 3bd13ae04ccc ("gpio: menz127: simplify error path and remove remove()")
> removed the .remove callback from menz127-gpio.c, not all mcb device
> drivers implement .remove callback.
>
> Remove .remove check to ensure all mcb device drivers can be loaded.
>
> I'll also add
>
> Fixes: 3bd13ae04ccc ("gpio: menz127: simplify error path and remove remove()")
>
>
> Thanks,
>
>     Johannes
>

Hi Johannes,

I noticed this patch is not uploaded yet.

I can submit it again changing the commit message as you commented above.

Thank you,

Javier R.