# Fan no longer turns on after kernel upgrade

## miriya

I've recently done a kernel upgrade in the hopes of getting the newer versions of X to work.  While X is mostly working, I've now come across another problem.  One of my fans isn't turning on when the computer gets hot.  I'm easily reaching 78C in temperature, and this seems rather unsafe to me.  During the BIOS self-check during bootup, I can hear the fan turn on to its maximum, so I don't believe it's a hardware problem.  I'm guessing I messed something up in the kernel config.  The computer is an Inspiron 700m and I'm running kernel 2.6.38-gentoo-r6.  I would post my .config file but I'm not sure how to do it without it taking up the whole post.  [/list]I have a few other X and sound problems, but I don't want to spend a lot of time emerging things if my computer might overheat.

I'd appreciate any help.  Thank you.

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## keenblade

Hi, miriya. I suggest to use one of  Pappy's Kernel Seeds as kernel config. And post the problems and configs in the related thread called

Pappy's Kernel Seeds Part IV. Pappy is a genius about kernel problems. Use http://pastebin.com/ to post your config files.

Follow his kernel documentation and grab a kernel config file here.

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## aCOSwt

Which kernel version did you upgrade from ?

The BIOS generally gets the possibility to control the fans.

Linux kernel gets that capability too via components such as smbus drivers. Components you can control from userspace.

In the past, both programs (the BIOS and smbus related thingies) could access the physical device concurrently.

This has (rightly) not been considered safe and as a default, linux kernel drivers now refuse to load if they detect that something is already accessing the device. This, in turn, preventing any control from userspace.

I suggest you check in your system logs for some report about conflicting ACPI regions. This would confirm that you hit this particular case.

If you are in this case then you can :

Either correctly configure your BIOS for adequate and autonomous monitoring of fans and then forget about everything else.

Or (not recommended) restore the previous behavior, that is to say allow both programs to control the same device by booting with the acpi_enforce_resources=lax option.

I do insist : The latter, likely to restore the behavior you might be used to, is rightly not recommended.

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## miriya

Thanks for the suggestion about the kernel seeds.  I'll definitely take a look and see if I can rebuild it correctly.  I'm upgrading from 2.6.30-gentoo-r8 to 2.6.38-gentoo-r6.  My primary reason for upgrading was that I wanted to use the newer 1.10 X (or really anything newer than the obsoleted 1.65-r1 which I had been using).  I wanted to switch to the built-in video.  Unfortunately, X is really giving me trouble.  I'd love to do more work to fix it, but with the computer overheating, I can't.

I've never had userspace control of the fans.  Before there wasn't any trouble in keeping it at a cool enough temperature.  I only know it works because it spins up during bootup.  Now the computer is sporadically freezing and the fan doesn't turn on once linux has booted.

My current kernel .config is here:  http://pastebin.com/ZtNj44kq

Thank you!

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## Chiitoo

Some thoughts: You mention hearing the fan spin-up, when does it exactly slow down?

Or does it actually stop completely?

Which fan is it?

I would still check the fan physically; perhaps the bearings are going bad and/or it is really dusty, which might prevent the fan from spinning at lower speeds (though if the scaling works correctly, at higher temperatures it should be able to spin again as you do hear it spin at POST, and as you said, it did work fine before?

I think the other guys are more to the right direction on this, though.

Good luck, I hope you are able to figure it out soon!

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## miriya

I've done some reading, and it looks like the Intel 855GM card is no longer supported by the newer drivers.  I've downgraded my kernel and reverted back to the old version of X which would sporadically lock-up without notice.  I don't anticipate support magically returning, so I expect not to be upgrading again anytime soon.

The computer is still running hot when I compile something or play videos, so I'll check out the fan and see if it's overly dusty.  I don't think the fan is worn down.  I replaced it about a year ago when the old fan was making loud noises while running, and the new one was doing fine until recently.  It has gotten quite hot in my AC-less apartment, so it's possible I've had a problem with the fan for a while and simply never noticed, or it's actually working correctly and it's just been exceedingly hot.  In the meantime, not running anything cpu-heavy and letting cpufreq throttle down the speed seems to be working.  I can run my day-to-day tasks without the lock-ups.  I'll update here if it does indeed turn out that my fan is just clogged.

Thank you for all your help!

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