Date: Mon, 6 Mar 2017 14:34:06 +0100
From: Michal Hocko <mhocko@kernel.org>
To: Daniel Vetter <daniel@ffwll.ch>
Cc: Laura Abbott <labbott@redhat.com>,
        Sumit Semwal <sumit.semwal@linaro.org>,
        Riley Andrews <riandrews@android.com>, arve@android.com,
        romlem@google.com, devel@driverdev.osuosl.org,
        linux-kernel@vger.kernel.org, linaro-mm-sig@lists.linaro.org,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        linux-arm-kernel@lists.infradead.org, linux-media@vger.kernel.org,
        dri-devel@lists.freedesktop.org, Brian Starkey <brian.starkey@arm.com>,
        Daniel Vetter <daniel.vetter@intel.com>,
        Mark Brown <broonie@kernel.org>,
        Benjamin Gaignard <benjamin.gaignard@linaro.org>, linux-mm@kvack.org
Subject: Re: [RFC PATCH 00/12] Ion cleanup in preparation for moving out of
 staging
Message-ID: <20170306133406.GD27953@dhcp22.suse.cz>
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On Mon 06-03-17 11:40:41, Daniel Vetter wrote:
> On Mon, Mar 06, 2017 at 08:42:59AM +0100, Michal Hocko wrote:
> > On Fri 03-03-17 09:37:55, Laura Abbott wrote:
> > > On 03/03/2017 05:29 AM, Michal Hocko wrote:
> > > > On Thu 02-03-17 13:44:32, Laura Abbott wrote:
> > > >> Hi,
> > > >>
> > > >> There's been some recent discussions[1] about Ion-like frameworks. There's
> > > >> apparently interest in just keeping Ion since it works reasonablly well.
> > > >> This series does what should be the final clean ups for it to possibly be
> > > >> moved out of staging.
> > > >>
> > > >> This includes the following:
> > > >> - Some general clean up and removal of features that never got a lot of use
> > > >>   as far as I can tell.
> > > >> - Fixing up the caching. This is the series I proposed back in December[2]
> > > >>   but never heard any feedback on. It will certainly break existing
> > > >>   applications that rely on the implicit caching. I'd rather make an effort
> > > >>   to move to a model that isn't going directly against the establishement
> > > >>   though.
> > > >> - Fixing up the platform support. The devicetree approach was never well
> > > >>   recieved by DT maintainers. The proposal here is to think of Ion less as
> > > >>   specifying requirements and more of a framework for exposing memory to
> > > >>   userspace.
> > > >> - CMA allocations now happen without the need of a dummy device structure.
> > > >>   This fixes a bunch of the reasons why I attempted to add devicetree
> > > >>   support before.
> > > >>
> > > >> I've had problems getting feedback in the past so if I don't hear any major
> > > >> objections I'm going to send out with the RFC dropped to be picked up.
> > > >> The only reason there isn't a patch to come out of staging is to discuss any
> > > >> other changes to the ABI people might want. Once this comes out of staging,
> > > >> I really don't want to mess with the ABI.
> > > > 
> > > > Could you recapitulate concerns preventing the code being merged
> > > > normally rather than through the staging tree and how they were
> > > > addressed?
> > > > 
> > > 
> > > Sorry, I'm really not understanding your question here, can you
> > > clarify?
> > 
> > There must have been a reason why this code ended up in the staging
> > tree, right? So my question is what those reasons were and how they were
> > handled in order to move the code from the staging subtree.
> 
> No one gave a thing about android in upstream, so Greg KH just dumped it
> all into staging/android/. We've discussed ION a bunch of times, recorded
> anything we'd like to fix in staging/android/TODO, and Laura's patch
> series here addresses a big chunk of that.

Thanks for the TODO reference. I was looking exactly at something like
that in drivers/staging/android/ion/. To bad I didn't look one directory
up.

Thanks for the clarification!

-- 
Michal Hocko
SUSE Labs