Hi,
I observed something very similar this after a jessie -> stretch
dist-upgrade. My whole failing logfile is attached, and the gist of the
problem was in these errors:
[...]
[ 5115.028] (EE) systemd-logind: failed to get session: PID 4398 does not belong to any known session
[...]
[ 5116.097] (EE) modeset(0): drmSetMaster failed: Permission denied
[ 5116.097] (EE)
[ 5116.097] (EE) AddScreen/ScreenInit failed for driver 0
[...]
The first error appeared to be the root cause - it was caused by not reading
through
https://www.debian.org/releases/stable/amd64/release-notes/ch-whats-new.en.html#x-no-longer-requires-root
where it said that the new way needs libpam-systemd
Nothing had installed that package in my dist-upgrade, probably because
I didn't choose to observe Recommends.
After installing that and rebooting, everything was fine and Xorg runs as
my own user, yay.
I'll also note here that my first searches for the latter error message
had produced a workaround - installing xserver-xorg-legacy and setting
needs_root_rights=yes in Xwrapper.config. But that result is obviously
inferior.
It would be much better if the Xorg modesetting error messages were somewhat
clearer as to what actually went wrong.
It looks like the defaults excluded the intel driver as such:
[ 5115.616] (==) Matched nouveau as autoconfigured driver 0
[ 5115.616] (==) Matched nv as autoconfigured driver 1
[ 5115.616] (==) Matched modesetting as autoconfigured driver 2
[ 5115.616] (==) Matched fbdev as autoconfigured driver 3
[ 5115.616] (==) Matched vesa as autoconfigured driver 4
When it worked, driver 2 actually seems to have reported:
[ 20.775] (II) modeset(0): [DRI2] Setup complete
[ 20.775] (II) modeset(0): [DRI2] DRI driver: i965
[ 20.775] (II) modeset(0): [DRI2] VDPAU driver: i965
This is counterintuitive given that I have xserver-xorg-video-intel
installed. If the intel driver is installed, that should provide
at least some sort of a hint to the Xorg server on runtime.
Maybe to include it in the list of defaults? I don't have several of the
above drivers installed and these particular wrong defaults merely lead to
more redundant error output...
If not that, then perhaps the modesetting driver should tell the user
that it tried to take command over these drivers, but that perhaps its
failure should not be completely fatal?
Arguably the situation is made complex by the fact that these laptops
have two GPUs, the Intel and the Nvidia one, and so both the users and
the software are more likely to be confused by default.
--
2. That which causes joy or happiness.
Attachment:
Xorg.0.log.old
Description: application/trash