gnome-shell crash: segfault at 50 ip 00007f2bd6028b05 sp 00007fffbb999068 error 4 in libcogl.so.9.1.0

[JulioHM]

I have just installed a fresh system with Ubuntu 12.04 LTS, and I am unable to use Unity 3D or Gnome3 with visual effects on my laptop. I can only use Unity 2D or Gnome Classic (no effects).

Once I login with visual effects, none of the window decorations appear, gnome-shell does not load, and the desktop is unsable. I am only able to click/navigate into folders because there is a directory in the desktop which I can open... I can't even get screenshot of what it looks like, since the keyboard never gets focus to type anything.

From /var/log/syslog, I can see the following errors, which I believe are related.

Apr 28 11:44:31 juliohmnote kernel: [ 1447.361473] gnome-shell[5366]: segfault at 50 ip 00007f0826023b05 sp 00007fff78bc14d8 error 4 in libcogl.so.9.1.0[7f0825fd8000+83000]
Apr 28 11:44:32 juliohmnote gnome-session[5290]: WARNING: Application 'gnome-shell.desktop' killed by signal
Apr 28 11:44:34 juliohmnote kernel: [ 1450.190498] gnome-shell[5460]: segfault at 50 ip 00007f09968a5b05 sp 00007fffb64f2a68 error 4 in libcogl.so.9.1.0[7f099685a000+83000]
Apr 28 11:44:35 juliohmnote gnome-session[5290]: WARNING: Application 'gnome-shell.desktop' killed by signal
Apr 28 11:44:35 juliohmnote gnome-session[5290]: WARNING: App 'gnome-shell.desktop' respawning too quickly
Apr 28 11:44:35 juliohmnote gnome-session[5290]: CRITICAL: We failed, but the fail whale is dead. Sorry....
Apr 28 11:44:59 juliohmnote blueman-mechanism: Exiting
Apr 28 11:45:37 juliohmnote kernel: [ 1513.152459] gnome-shell[5626]: segfault at 50 ip 00007f05ac0f2b05 sp 00007fffeb053d08 error 4 in libcogl.so.9.1.0[7f05ac0a7000+83000]

I'll be glad to collect any files or command line outputs that may be of help for this, so let me know. In my ignorance, all I can think of right now is an lspci dump of the hardware I have (see attached).

Thank you for the help.

[JulioHM (jhm-g)]

I have just confirmed this is the same problem discussed

here...
http://ubuntuforums.org/showthread.php?t=1966002&page=2

and here...
https://answers.launchpad.net/ubuntu/+question/194996

I found the exact same crash from Compiz on /var/log/syslog.

May 4 02:16:06 juliohmnote kernel: [ 659.671328] compiz[11423]: segfault at 7f34b4c7c400 ip 00007f34e4eeb7e5 sp 00007fff2ea202c8 error 4 in libc-2.15.so[7f34e4e5a000+1b3000]

So, this is not a gnome-sheel problem after all. Turns out, the current NVIDA driver (version 295.49) which is shipped with Precise has a known bug that needs to be fixed in the next releases. In the meantime, it is possible to downgrade to version 295.33 and use the driver without reproducing this particular problem.

To downgrade:

# Uninstall the current nvidia driver
sudo apt-get purge nvidia-current

# Download the previous version of this driver
http://us.download.nvidia.com/XFree86/Linux-x86_64/295.33/NVIDIA-Linux-x86_64-295.33.run

# Switch to tty1 (CTRL+ALT+F1)
# This needs to be done without lightdm running
sudo stop lightdm

# Make sure you have build-essential installed and the current linux headers
# The installation will try to build and install kernel modules
sudo sh NVIDIA-Linux-x86_64-295.33.run

# Restart lightdm
sudo start lightdm

Enjoy Unity with visual effects.

[JulioHM (jhm-g)]

This is a bug on the current nvidia driver. Instructions on workaround posted.

[daigoro (daigorocub)]

I also have this problem but my graphics driver is intel (xserver-xorg-video-intel) . My version is 2:2.17.0-1ubuntu4.4 and I already tried the 2:2.20 version with no success.

Any recomendations?