Kernel problem with multiseat on one card

[Gert Vanhaerents]

>>> Hi Kernel list,
>>> I'm the IT person of a school, earlier we used multiseatcomputers 
>>> for the
>>> school, i have maded with a XGL implementation and it works fine but 
>>> not so
>>> fantastic. The school wants that i build new computers but the XGL 
>>> project
>>> is too outdated so i can't use it anymore.
>>>
>>> How can i make a multiseatcomputer with more then one user on one 
>>> card with
>>> systemd? I have asked already to the makers of systemd but they said 
>>> it's a
>>> kernel problem.
>>>
>>> With Systemd loginctl and the nouveau drivers you have this:
>>>
>>> ─/sys/devices/pci0000:00/0000:00:03.1/0000:08:00.0/drm/card0
>>>            │ [MASTER] drm:card0
>>>            │
>>> ├─/sys/devices/pci0000:00/0000:00:03.1/0000:08:00.0/drm/card0/card0-DVI-D-1 
>>>
>>>            │ │ [MASTER] drm:card0-DVI-D-1
>>>            │
>>> ├─/sys/devices/pci0000:00/0000:00:03.1/0000:08:00.0/drm/card0/card0-HDMI-A-1 
>>>
>>>            │ │ [MASTER] drm:card0-HDMI-A-1
>>>            │
>>> └─/sys/devices/pci0000:00/0000:00:03.1/0000:08:00.0/drm/card0/card0-VGA-1 
>>>
>>>            │   [MASTER] drm:card0-VGA-1
>>> ├─/sys/devices/pci0000:00/0000:00:03.1/0000:08:00.0/drm/renderD128
>>>            │ drm:renderD128
>>> ├─/sys/devices/pci0000:00/0000:00:03.1/0000:08:00.0/graphics/fb0
>>>            │ graphics:fb0 "nouveaudrmfb"
>>>
>>> So it will be:
>>>
>>> loginctl attach seat1 
>>> /sys/devices/pci0000:00/0000:00:03.1/0000:08:00.0/drm/card0/card0-VGA-1
>>>
>>> For the seat1 (the VGA d-sub output for seat1 and the other HDMI 
>>> output for
>>> seat0) and of course the mouse and keyboard.
>>>
>>> When you do this, all the graphics outputs are on the second seat 
>>> (seat1)
>>> and not anymore on the first seat. So i need to move only the VGA 
>>> output to
>>> seat1 and not all the outputs.
>> Do you expect that GUI output is on both seats?
>
> I want the result that i have one seat (seat0) on the VGA/D-sub output 
> of the graphic card
>
> a second seat (seat1) on the HDMI output of the graphic card
>
> and a third seat (seat2) on the DVI output of the graphic card
>
> In theory it should work with the following:
> loginctl attach seat1 
> /sys/devices/pci0000:00/0000:00:03.1/0000:08:00.0/drm/card0/card0-HDMI-A-1
>
> loginctl attach seat2 
> /sys/devices/pci0000:00/0000:00:03.1/0000:08:00.0/drm/card0/card0-DVI-D-1
>
> But when i do this all the outputs will be used on seat2 (because they 
> do all the outputs automaticly to the latest attached seat)
>
>
>>>
>>> When i install the proprietary Nvidia drivers, i have the following:
>>>
>>> [MASTER] pci:0000:08:00.0
>>>            │ 
>>> ├─/sys/devices/pci0000:00/0000:00:03.1/0000:08:00.0/drm/card0
>>>            │ │ [MASTER] drm:card0
>>>            │
>>> └─/sys/devices/pci0000:00/0000:00:03.1/0000:08:00.0/drm/renderD128
>>>            │   drm:renderD128
>>>
>>> ─/sys/devices/platform/efi-framebuffer.0/graphics/fb0
>>>            │ graphics:fb0 "EFI VGA"
>>>
>>> So no VGA, DVI or HDMI items.
>> Then report to the GitHub tracker [1].
>>
>> Thanks.
>>
>> [1]: https://github.com/NVIDIA/open-gpu-kernel-modules/issues
>>