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Date:   Sat, 10 Aug 2019 01:22:00 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     Gerd Hoffmann <kraxel@redhat.com>
Cc:     dri-devel@lists.freedesktop.org, David Airlie <airlied@linux.ie>,
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        "open list:VIRTIO GPU DRIVER" 
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Subject: Re: [PATCH] drm/virtio: use virtio_max_dma_size
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On Thu, Aug 08, 2019 at 05:34:45PM +0200, Gerd Hoffmann wrote:
> We must make sure our scatterlist segments are not too big, otherwise
> we might see swiotlb failures (happens with sev, also reproducable with
> swiotlb=force).

Btw, any chance I could also draft you to replace the remaining
abuses of swiotlb_max_segment and swiotlb_nr_tbl in drm with proper
dma level interface?