compiz works, but not with gdm

[renauldo]

As long as I start an xsession with something other than GDM, I can get effects (compiz) to start. If I start via GDM, I get the errors about DRI not being loaded.

I can't see how this can be -- asfaict, GDM is using the same /etc/X11/xorg.conf as xinit and friends... Anyone have any idea why GDM is making things crazy?

Thanks,
Renauldo

[renauldo]

I just upgraded kernel and nvidia drivers that became available yesterday, and still have this issue: in order to compiz|DRI to work, I have to '/etc/init.d/gdm stop', 'xinit', and then in the controlling term startup 'gnome-session'.

Why would this not work when X is started from gdm? I don't see any crazy strings in the args gdm passes to X (in ps axf).

[renauldo]

output from compiz-check via gdm gnome session:

Distribution: Ubuntu 8.04
Desktop environment: GNOME
Graphics chip: nVidia Corporation GeForce 7100 GS (rev a1)
Driver in use: nvidia
Rendering method: Nvidia

Checking if it's possible to run Compiz on your system...

Checking for texture_from_pixmap... [ FAIL ]
Checking for non power of two support... [ FAIL ]
Checking for composite extension... [ OK ]
Checking for FBConfig... [ OK ]
Checking for hardware/setup problems... [ OK ]


output via failsafe gdm session, after running 'gnome-session' in the control terminal is identical, except that the first two checks come out "[ OK ]" and compiz works just fine.

What in the world is messing up the gdm gnome session selection? Where can I check what gets executed when this is selected?

Note: it is messed up for all users, even pristine ones that were just created. From failsafe, compiz works fine.

glxgears gives an error about DRI not being present.

Anyone, help?