Re: [virtio-dev] [PATCH 2/2] drm/virtio: add iommu support.

From: Gerd Hoffmann
Date: Wed Sep 12 2018 - 03:25:47 EST


Hi,

> I attempted to fix it in the ttm layer and here is the discussion
> https://lore.kernel.org/lkml/b44280d7-eb13-0996-71f5-3fbdeb466801@xxxxxxx/
>
> The ttm maintainer Christian is suggesting to map and set ttm->pages as decrypted
> right after ttm->pages are allocated.
>
> Just checking with you guys maybe there is a better way to handle this in
> the virtio gpu layer instead of the common ttm layer. Could you guys shine some
> light on this? Thanks.

I think the tty layer is the right place to fix this. virtio just calls
down to ttm for mappings. I think virtio should just hint to ttm using
a flag in some struct, probably ttm_buffer_object or
ttm_mem_type_manager, that the objects need decrypted mappings.

cheers,
Gerd