non-privileged X and non-free drivers

[Vincent Cheng]

Hi Julien,

On Tue, Aug 25, 2015 at 3:53 PM, Luca Boccassi <luca.boccassi at gmail.com> wrote:
> On Tue, 2015-08-25 at 12:44 +0200, Julien Cristau wrote:
>> Hi,
>>
>> I'm about ready to upload new xorg-server and xorg packages from
>> experimental to unstable.  In these new versions, the /usr/bin/X setuid
>> wrapper previously shipped in xserver-xorg is gone, and a new
>> xserver-xorg-legacy binary package is provided that includes (hopefully)
>> equivalent functionality.
>>
>> Can you please let me know if your driver requires that X runs as root
>> nowadays?  If so, you will likely need to add a dependency on
>> xserver-xorg-legacy.
>
> Hello Julien,
>
> Thanks for the heads-up!
>
> Andreas and Vincent will know more than me about specific nvidia quirks.

I don't know anything in particular about the proprietary driver's
quirks that's not mentioned in the documentation; the only thing the
docs mention regarding requiring a setuid root X wrapper can be found
at [1], i.e. nvidia needs X to run as root only to enable device node
creation (/dev/nvidia*) and kernel module loading, but both are
currently handled by the nvidia packages themselves, so I don't think
we'd need to depend on the existing setuid wrapper.

> But I did a quick test, and, assuming I'm doing everything right, it
> seems that nvidia-driver (352.30-1 from experimental) works fine when
> Xorg is not ran as root.
>
> I installed the following from experimental:
>
> xorg
> xserver-xorg
> xserver-xorg-core
> xserver-xorg-common
> x11-common
>
> Rebooted, killed my gdm3 session (Gnome 3.14, I'm running Jessie) and
> ran "startx" from tty1 as normal user:
>
> $ ps aux | grep -i xorg
> luca      2448  3.3  0.8 184220 65420 tty1     S    23:29
> 0:03 /usr/lib/xorg/Xorg -nolisten tcp :0 vt1
> -auth /tmp/serverauth.p6yaPygdsO
>
> X session came up just fine with the right configuration, 2D and 3D
> applications ran ok as well. Didn't spot any error in the journal.
>
> Anything else I should test/look for? Any other package I should install
> from experimental?

Luca, just a thought, were you testing with an Nvidia Optimus-enabled
system with bumblebee installed? Doing so means the primary X display
is driven by intel not nvidia...although I'm not sure if this actually
makes a difference or not regarding the setuid wrapper.

Regards,
Vincent

[1] http://us.download.nvidia.com/XFree86/Linux-x86/352.30/README/faq.html