Re: [Feature request] Multiple X servers on one graphics card?

["Prof. Dr. Klaus Kusche" <klaus.kusche@computerix.info>]

On 2011-08-01 22:22, Alan Cox wrote:
> There are also some interesting security issues with a lot of GPUs where
> you'd be very very hard pushed to stop one task spying on the display of
> another as there isn't much in the way of MMU contexts on the GPU side.
>
> Alan

But I believe this is a problem of all approaches which provide
multiple hardware-accelerated (or Xv-enabled) seats on a single GPU,
no matter if based on multiple DRM devices, on Xephyr or Xnest
with some kind of OpenGL or DRI passthrough, or on Wayland:
If one has direct access to the graphics engine, he also can access
any video memory he wants.

Hence, that's no argument against multiple DRM devices on a single card,
because the other solutions suffer from the same problem.

In the long term, it needs to be fixed,
but in a classroom environment, that's not my primary concern
(and I believe 90 % of all multiseat installations
will be classroom or home environments).

Klaus.

-- 
Prof. Dr. Klaus Kusche
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