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From:   Christoph Hellwig <hch@lst.de>
To:     thellstrom@vmware.com
Cc:     linux-graphics-maintainer@vmware.com,
        dri-devel@lists.freedesktop.org, iommu@lists.linux-foundation.org,
        linux-kernel@vger.kernel.org
Subject: fix DMA ops layering violations in vmwgfx
Date:   Sat,  5 Jan 2019 09:01:04 +0100
Message-Id: <20190105080108.14837-1-hch@lst.de>
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Hi Thomas,

vmwgfx has been doing some odd checks based on DMA ops which rely
on deep DMA mapping layer internals, and I think the changes in
Linux 4.21 finally broke most of these implicit assumptions.

The real fix is in patch 3, but I think the others are important
to make it clear what is actually going on.