Realtime kernel forces low-graphics mode with nvidia

[Philip]

Ubuntu Version: Hardy Heron.

The linux-rt kernel (specifically 2.6.24-21-rt) refuses to work with the nvidia driver. Before the login screen appears, the screen flickers and then presents me with a low-graphics mode at 800x600 and gives me a window to choose my monitor and video driver. My (working) driver in the generic version is nvidia. When I choose nvidia and do a test, the screen blacks out for a few seconds, and then comes back to tell me the test failed and I should select another driver. Not even the nv driver works. The last realtime kernel that worked correctly with regard to the nvidia driver was the 2.6.24-16-rt kernel, and I have to keep that old kernel around.

I am running Gnome with compiz. Maybe this is the same or similar issue to https://bugs.launchpad.net/ubuntu/+source/linux-meta/+bug/152258

[Alessio Igor Bogani (abogani)]

@Philip,

Could you post the output of the 'dpkg -l | grep linux-restricted-modules' ?

Thanks!

[Philip (rocketman768)]

ii linux-restricted-modules 2.6.24.21.23 Generic Linux restricted modules.
rc linux-restricted-modules-2.6.20-16-realtime 2.6.20.5-16.28 Non-free Linux 2.6.20 modules on x86/x86_64
rc linux-restricted-modules-2.6.22-14-generic 2.6.22.4-14.10 Non-free Linux 2.6.22 modules on x86/x86_64
rc linux-restricted-modules-2.6.22-14-rt 2.6.22.4-14.10 Non-free Linux 2.6.22 modules on Realtime ke
ii linux-restricted-modules-2.6.24-16-generic 2.6.24.12-16.34 Non-free Linux 2.6.24 modules on x86/x86_64
ii linux-restricted-modules-2.6.24-16-rt 2.6.24.12-16.34 Non-free Linux 2.6.24 modules on x86/x86_64
ii linux-restricted-modules-2.6.24-17-generic 2.6.24.12-17.36 Non-free Linux 2.6.24 modules on x86/x86_64
ii linux-restricted-modules-2.6.24-17-rt 2.6.24.12-17.36 Non-free Linux 2.6.24 modules on x86/x86_64
ii linux-restricted-modules-2.6.24-18-generic 2.6.24.13-18.41 Non-free Linux 2.6.24 modules on x86/x86_64
ii linux-restricted-modules-2.6.24-18-rt 2.6.24.13-18.41 Non-free Linux 2.6.24 modules on x86/x86_64
ii linux-restricted-modules-2.6.24-19-generic 2.6.24.13-19.45 Non-free Linux 2.6.24 modules on x86/x86_64
ii linux-restricted-modules-2.6.24-19-rt 2.6.24.13-19.45 Non-free Linux 2.6.24 modules on x86/x86_64
ii linux-restricted-modules-2.6.24-21-generic 2.6.24.14-21.51 Non-free Linux 2.6.24 modules on x86/x86_64
ii linux-restricted-modules-2.6.24-21-rt 2.6.24.14-21.51 Non-free Linux 2.6.24 modules on x86/x86_64
ii linux-restricted-modules-common 2.6.24.14-21.51 Non-free Linux 2.6.24 modules helper script
ii linux-restricted-modules-generic 2.6.24.21.23 Restricted Linux modules for generic kernels
ii linux-restricted-modules-rt 2.6.24.21.23 Restricted Linux modules for rt kernels

[Alessio Igor Bogani (abogani)]

@Philip,

Could you execute an 'sudo depmod -a' so reboot and test again, please?

Thanks!

[Philip (rocketman768)]

Alessio,

I ran depmod as you suggested, but I still get the "ubuntu is in low-graphics mode" screen before login. Thanks for helping btw!

[Juanelas (juanelas)]

1. Switch to a text console (crtl-alt-f2)
2. Log in
3. Stop GDM: $ sudo /etc/init.d/gdm stop
4. Install envying (an installer for graphic card drivers): $ sudo apt-get install envying-core
   (you will need to previously setup the network or just install envying-core when login with the standard kernel)
5. Compile and install appropriate drivers: $ sudo envyng -t
   (just follow the instructions)
6. Restart

[Philip (rocketman768)]

While the envyng process worked, it had the side-effect of causing the exact same graphics problem with my generic kernel. I would prefer a solution such that I can have proper graphic support for the 2 kernels at the same time.

[Alessio Igor Bogani (abogani)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. It would help us greatly if you could test with Jaunty Jackalope! Thanks again and we appreciate your help.

[Philip (rocketman768)]

I upgraded to Intrepid last week, and the problem has disappeared.

[Alessio Igor Bogani (abogani)]

This bug report is being closed due to your last comment regarding this being fixed with an update. For future reference you can manage the status of your own bugs by clicking on the current status in the yellow line and then choosing a new status in the revealed drop down box. You can learn more about bug statuses at https://wiki.ubuntu.com/Bugs/Status . Thank you again for taking the time to report this bug and helping to make Ubuntu better. Please submit any future bugs you may find.

[Lukáš Zapletal (lzap)]

But in Jaunty it appears again for me :-(

[Trystan (trystan-trystan)]

I would really like to see this re-opened. The problem continues to effect 10.04. The issue is that the RT kernel tries to load the nvidia kernel module for the standard kernel. If you work around the issue by recompiling the module while booted in the RT kernel, then it doesn't work when you switch back to the standard kernel. So it seems that multiple kernels can't coexist when using nvidia; big usability problem.