Re: [PATCH] kbuild: make module name conflict fatal error

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Tue, Jun 09, 2020 at 09:51:46AM +0200, Arnd Bergmann wrote:
> On Tue, Jun 9, 2020 at 8:20 AM Greg Kroah-Hartman
> <gregkh@linuxfoundation.org> wrote:
> >
> > On Sun, Jun 07, 2020 at 07:02:56PM -0700, Guenter Roeck wrote:
> > > Hi,
> > >
> > > On Mon, May 11, 2020 at 01:21:49PM +0900, Masahiro Yamada wrote:
> > > > I think all the warnings have been fixed by now. Make it a fatal error.
> > > >
> > >
> > > Not entirely. With this patch in the tree, I get:
> > >
> > > Building sparc64:allmodconfig ... failed
> > > --------------
> > > Error log:
> > > error: the following would cause module name conflict:
> > >   drivers/char/adi.ko
> > >   drivers/input/joystick/adi.ko
> > > make[1]: *** [modules_check] Error 1
> > > make[1]: *** Waiting for unfinished jobs....
> > > make: *** [__sub-make] Error 2
> > >
> > > Reverting this patch fixes the problem.
> >
> > As it doesn't look like either of these drivers can be "auto-loaded"
> > based on hardware detection, I don't know what to suggest as for
> > renaming either of them.
> >
> > Any ideas?
> 
> I see zero chance of a kernel actually needing to provide both drivers,
> given that the hardware is 20 years apart and gameports are almost
> exclusive to x86 PCs. How about an ugly hack:
> 
> diff --git a/drivers/input/joystick/Kconfig b/drivers/input/joystick/Kconfig
> index 940b744639c7..6f73f02059b5 100644
> --- a/drivers/input/joystick/Kconfig
> +++ b/drivers/input/joystick/Kconfig
> @@ -45,6 +45,7 @@ config JOYSTICK_A3D
>  config JOYSTICK_ADI
>         tristate "Logitech ADI digital joysticks and gamepads"
>         select GAMEPORT
> +       depends on ADI!=m # avoid module name conflict
>         help
>           Say Y here if you have a Logitech controller using the ADI
>           protocol over the PC gameport.
> 
>       Arnd

Looks sane to me, thanks!

greg k-h