Sharing a KMS device

[Troll Berserker]

On 18/09/18 22:49, Keith Packard wrote:
> Troll Berserker <berserker.troll at yandex.com> writes:
> 
>> Is it theoretically possible to implement a driver (let's call it
>> shared-modesetting) which will offload mode setting to a helper daemon
>> (drmMaster) thus allowing to run multiple Xorg servers on one DRM
>> device? (provided that there are enough CRTCs (?) available).
> 
> We've recently add a new technique in DRM called 'leasing', which allows
> you to create a new DRM controller for a subset of the available resources.
> 

Cool. In your talk you even mentions multiseating.
AFAIU with this technique one doesn't get multiple /dev/dri/card* for a GPU out of the box, so it is not possible to use unmodified modesetting driver to run multiple X servers.