CPU frequency scaling problem - laptop users, please check this

[Rashkae]

On 05/24/2011 02:17 PM, A. Kromic wrote:
>
> What I meant is this: my system's CPU scaling has worked and still works
> perfectly with all old kernels up to 2.6.32-24, with any kernel newer
> than that it doesn't work at all. I can reproduce it anytime, either
> chosing a kernel from GRUB, or by booting a live CD. Another fact
> perhaps worth noting is that it doesn't matter if it is a 32- or 64-bit
> Ubuntu - I've checked with both, and again the problem depends just on
> the kernel version.
>
> I don't quite get what the problem is, it seems it's quite rare. However
> so far, I couldn't find anything else but the kernel to blame, per the
> above mentioned fact. No amount of tinkering with other software (like
> acpi, cpu frequency managers etc.) not hardware (battery, BIOS options)
> showed any difference at all...
>
> And thanks again to everybody who tested!

Keep in mind that this problem is obviously not very widespread, and the 
people who can actually work on this kind of low level bug probably 
don't read Ubuntu list.  (heck, Ubuntu devs can't even figure out how 
floppy works.)

Since no one has stepped up here with suggestions to your particular 
situation, I wold suggest the following (if within your comfort zone of 
technical skills.)

Download and build the latest vanilla kernel from source, see if you can 
replicate the problem with that.

If it's already fixed with the new kernel, then just use that until 
Ubuntu catches up with that kernel version.

If the bug persists, report it, as well as any details of your hardware 
to the lkml.

I trust that once a bug of this nature is detailed on lkml, it will be 
worked on and patched very quickly, at which point, you can update the 
Ubuntu bug report with the patch that fixes the issue.