Strange acpi kernel output
 

This has stumped me for months and I am finally annoyed to the point to beg for help! I am using a custom compiled kernel with ACPI support build in. No extra modules, nothing. I tried building in support for the video, fan, etc but I still got the same errors. Every few hours, randomly it seems, I get this output from dmesg:

I am using a Pentium 4 system. Few years old, nothing ancient. I am not sure what information others may need to lend a hand but any information would be appreciated.

http://lists.freebsd.org/pipermail/f...er/000868.html

Have a look at this link for starters. I guess you are using a laptop machine, correct?
From what I read on a bunch of things I googled, the problem you are having is indeed related to the ACPI system, in your case specifically to the processor Thermal Zone (hence the _TZ_ stuff), and possibly also related to the computers fan speed not adjusting properly/responding to requests properly during power-saving and resume modes. It happens every once in a while, because the machine or OS is attempting to change power-states, and is having trouble doing it.
Personally, I cannot advise what you can do about this, but here are some hints/ideas as to what to try, based ONLY on what I read. I don't have a laptop, and my desktop's ACPI works fine, so please do your own research first, as I cannot be responsible for what you do to your machine:
1 - Google small pieces of the error messages you have there, for loads of threads about other people with the same issues. A lot of the threads I found were in Spanish, but there are a lot of English ones too. Many of them are bug reports and threads in the kernel development mailing list, but you can follow the conversations easily enough, and perhaps put together some ideas of what else to try.
2 - Turn off ACPI. I know, stupid answer, but it's an easy fix, but an undesirable one, so seriously, if you are using a laptop, I don't recommend this approach. It *would* prove that this is indeed an ACPI problem, but I think there's little doubt of that anyways.
3 - Recompile your kernel. First research as much as you can about the possible settings you can use for the ACPI-enabled parts of your computer: ie; fan; clock speed; fan speed; lid up/down; power button; display power-saving; power-down/resume modes; etc.. Next, make your kernel with every possible ACPI option you think may be relevant to your machine, and build them all as modules. this will undoubtedly take a LOAD of experimentation and testing, so don't expect to find the exact problem/solution overnight. It may take days, or weeks, of watching the machine perform, and watching for the occurrence of the errors and what exactly the machine was doing at the time.
Experiment with adding different modules to the kernel.
For example, if you are running error free, then add another module, and watch it for long enough to determine if it is still running error free. If it is, and it is still operating perfectly in other respects, then add another module. Repeat.
If/When the errors stop or start happning, you will know what module is contributing to the issue, and thus know what ACPI mechanism is causing the problem. :) Then you will have a much more accurate idea of what you need to look for as far as patches, bug-fixes, work-arounds, etc..
Incidentally, what kernel are you using?? It is possible that an older or newer kernel does not have this problem, or that it has been fixed in a later release.
I wish I could give you an exact place to start looking, but this is the best I could find.
Best of luck, and if you need some help deciphering any info you find on the web that might help, feel free to ask.
Take care!

I am using a custom 2.6.20-7 kernel and the only ACPI option compiled into the kernel is enabling ACPI itself. No modules for fan, battery, nothing. I am starting to think that this may have something to do with my system overheating but I am not sure. I am looking into it.

Solved. Turned out to be an overheating issue. I have a mid case and have since purchase added a 450 w p/s, Nvidia 7800 gt, Audigy 2zs and a second drive. Its getting a little crowded I guess and my Geforce was almost cooking. I got a Zalman gpu cooler and a bigger case fan and I do not have any more errors.

Hey great news! Not often one actually finds it *really is* running hot, so nice work, and none too soon.. Time to get the ACPI all figured out, so you will know from here on in if there is ever another problem, before it's too late.