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Date: Mon, 17 Oct 2011 22:39:28 +0100
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Hugh Dickins <hughd@google.com>
Cc: Rob Clark <rob.clark@linaro.org>,
        Patrik Jakobsson <patrik.r.jakobsson@gmail.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Christoph Hellwig <hch@infradead.org>, greg@kroah.com,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH 34/49] gma500: the GEM and GTT code is device
 independant
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> It feels to me like GEM is pulling shmem in an ever more alien direction:
> these device constraints are so foreign to the nature of tmpfs; and
> beyond my expertise, so that I'd be ever more likely to make the wrong
> decisions (mixing swap and uncached pages? hmmm).

For the most part we fixed that. You can now have a GEM object that is
backed by a private memory object rather than having to be tmpfs.
GMA500 uses it to attach 'stolen' memory to GEM handles, and at least
one other pending submission uses it with a private CMA style allocator.

The gma500 report seems an odd one - no GMA500 box has >4GB memory so how
did the test code get a page that was unsuitable - is the test buggy ?

Alan