Re: [PATCH 2/2] nouveau: fix dependencies for DEVICE_PRIVATE

From: Jason Gunthorpe
Date: Fri May 08 2020 - 15:04:51 EST


On Fri, May 08, 2020 at 05:05:03PM +0200, Arnd Bergmann wrote:
> On Fri, May 8, 2020 at 5:00 PM Jason Gunthorpe <jgg@xxxxxxxxxxxx> wrote:
> >
> > On Fri, May 08, 2020 at 04:40:09PM +0200, Arnd Bergmann wrote:
> > > CONFIG_DEVICE_PRIVATE cannot be selected in configurations
> > > without ZONE_DEVICE:
> >
> > It is kind of unfortunate to lift dependencies from DEVICE_PRIVATE
> > into the users, is this really how kconfig is supposed to work or is
> > something else wrong here?
>
> Usually the problem is trying to use 'select' for something that can
> be done with 'depends on'. I have actually no idea what
> CONFIG_DEVICE_PRIVATE does, as it lacks a help text
> and is a rather generic term.

It is a sub mode of ZONE_DEVICE, ie DEVICE_PRIVATE turns on a certain
kind of ZONE_DEVICE page.

Both ZONE_DEVICE and DEVICE_PRIVATE are APIs families drivers use,
there is no reason for a user to select either of these directly.

Jason