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From:   Arnd Bergmann <arnd@arndb.de>
Date:   Fri, 8 May 2020 17:05:03 +0200
Message-ID: <CAK8P3a1vCx=XibDdoDqG9obpCFx0JCibAvcKFh6E7_NR_hJ03A@mail.gmail.com>
Subject: Re: [PATCH 2/2] nouveau: fix dependencies for DEVICE_PRIVATE
To:     Jason Gunthorpe <jgg@mellanox.com>
Cc:     Ben Skeggs <bskeggs@redhat.com>,
        Felix Kuehling <Felix.Kuehling@amd.com>,
        Christoph Hellwig <hch@lst.de>,
        John Hubbard <jhubbard@nvidia.com>,
        David Airlie <airlied@linux.ie>,
        Daniel Vetter <daniel@ffwll.ch>,
        Dan Williams <dan.j.williams@intel.com>,
        Ira Weiny <ira.weiny@intel.com>,
        dri-devel <dri-devel@lists.freedesktop.org>,
        ML nouveau <nouveau@lists.freedesktop.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
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On Fri, May 8, 2020 at 5:00 PM Jason Gunthorpe <jgg@mellanox.com> 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.

Would it be possible to decouple DEVICE_PRIVATE from ZONE_DEVICE?
It sounds like the first is related to the device model, while
the second is for memory management, so maybe the dependency
is not necessary.

       Arnd