CPU Frequency Scaling Monitor Applet does not allow me to change CPU Frequency (Ubuntu 8.10)

thank you for your bug report, could you try if that's still an issue in jaunty?

We are closing this bug report as it lacks the information, described in the previous comments, we need to investigate the problem further. However, please reopen it if you can give us the missing information and don't hesitate to submit bug reports in the future.

Sebastien and I exchanged email over this bug and he requested that I check with Jaunty which I did. The applet appeared to work and I sent him email about it.

I have reinstalled Jaunty on the same machine (Dell D630) and the applet has stopped working again. This time I have changed this report to a question rather than a bug and I would like to understand what is not working. Any help in debugging would be most appreciated.

What I find now is as follows.

apt-cache policy gnome-applets
gnome-applets:
  Installed: 2.26.1-0ubuntu1
  Candidate: 2.26.1-0ubuntu1
  Version table:
 *** 2.26.1-0ubuntu1 0
        500 http://us.archive.ubuntu.com jaunty-updates/main Packages
        100 /var/lib/dpkg/status
     2.26.0-0ubuntu4 0
        500 http://us.archive.ubuntu.com jaunty/main Packages

ls -l /usr/bin/cpufreq-selector
-rwsr-sr-x 1 root root 30656 2009-04-23 08:28 /usr/bin/cpufreq-selector

more /proc/cpuinfo
processor : 0
vendor_id : GenuineIntel
cpu family : 6
model : 15
model name : Intel(R) Core(TM)2 Duo CPU T7250 @ 2.00GHz
stepping : 13
cpu MHz : 2001.000
cache size : 2048 KB

Using cpufreq-selector from the command line, I (logged in as a user who is NOT root and who CANNOT ADMINISTER the system).

cpufreq-selector -f 800000
more /proc/cpuinfo
processor : 0
vendor_id : GenuineIntel
cpu family : 6
model : 15
model name : Intel(R) Core(TM)2 Duo CPU T7250 @ 2.00GHz
stepping : 13
cpu MHz : 800.000

In other words, I (logged in as amrith, not the root user, not an administrator) am able to use cpufreq-selector to update the scaling. And it works because cpufreq-selector has been setuid'ed correctly.

On the other hand, the CPU performance applet does not give me the ability to change the frequency.

NOTE:

If I login as the root user, the CPU performance applet works correctly.

The difference appears to be that as a non-root user, the CPU Frequency Scaling Monitor applet is not allowing me to adjust the scaling, just view it. But, as a root user, the CPU Frequency Scaling Monitor applet is working correctly.

What have I tried?

1. I tried to suid on /usr/lib/gnome-applets/cpufreq-applet

I can't launch the applet, it gives an error

2. I've tried to strace the applet

When logged in as the non-root user, I see nothing indicating an error.

How should I gather more information to help debug this?

As the bloke who entered this bug, I am marking it new. The explanation is below. Maybe it is a bug in some other part of the system, maybe it is not. I'll let someone else make that decision.

(a) The CPU Frequency scaling applet works as expected. You don't need to setuid on cpufreq-selector

(b) The issue I had was as described below.

To reproduce this problem, here are the required steps.

1. Perform an ubuntu installation
2. During the installation, when prompted for the name of the person using the system, provide a name (say user1)
3. After the installation, login as user "user1" and create a new user "user2" who is a "Desktop User"
4. Enable Administrator login (in login window properties)
5. Set a root password
6. Logout as user "user1"
7. Login as root
8. Delete user "user1"
9. Logout as user root
10. Login as user "user2"
11. Add CPU Scaling applet to bar. It will not work.

The reason appears to be that in order to work, the CPU applet (and a whole bunch of other things) attempt to validate that the "Desktop User" is a user who can perform administration. They look for the user who was setup during installation and not finding that user, they don't do anything. But, they also provide no errors, nor do they they attempt to use the "root" user.

This is most likely NOT a gnome-applets bug. Please reassign to the right place.

When you created the user that was unable to set the frequency, did you make it an admin user? It seems to work for me as long as the user is an admin, with lucid alpha 3+.

We are closing this bug report because it lacks the information we need to investigate the problem, as described in the previous comments. Please reopen it if you can give us the missing information, and don't hesitate to submit bug reports in the future. To reopen the bug report you can click on the current status, under the Status column, and change the Status back to New. Thanks again!.