Slackware current, kernel 2.6.32.7, cpu fan problem

giberg · 02-04-2010, 10:41 AM

After upgrading to kernel 2.6.32.7 in current, the cpu fan in my notebook stopped working. Cpu temperature is 0 C (obviously impossible).

After a system reboot it works but speed is constant and the temperature remains stable at 50 C...

thermal module is loaded...

I didn't see the fan module loaded so I tried to load it manually but nothing changes.

Any idea?

Are there any changes in kernel configuration?

giberg · 02-04-2010, 10:48 AM

I forgot a detail...

Acer Aspire 5720, Intel Core 2 Duo T7300

marnold · 02-04-2010, 12:52 PM

FWIW, I just upgraded my Slackware64 13.0 install using the 2.6.32.7 kernel and the generic config from -current. The only things I changed were building ext2,3,4 into the kernel itself so I didn't have to mess with an initrd. While I don't have a laptop, lm_sensors/gkrellm is reporting the same fan speeds, system temps for my Gigabyte P55a i5-750 system.

giberg · 02-06-2010, 08:00 AM

The fan seems to work when I reboot but only when the cpu has high temperatures.
However it doesn't work correctly.

Maybe the cpu temperature sensor is the problem.

niels.horn · 02-06-2010, 03:50 PM

The newer kernels (> 2.6.30 I think) have some problems with some sensors. Mine won't read the fan speed any longer.
I haven't had time to investigate much, but check your dmesg for errors at the end.

thatquietboy · 02-06-2010, 04:35 PM

Does the o/s even control the fan? I always assumed that it was just the bios reading the cpu's temperature.

niels.horn · 02-06-2010, 04:54 PM

Correct, the bios controls the fan, but the sensor tell the OS what the temperature and fan speed is.
Without the sensors working (or actually, the driver that reads the sensors), the OS might report temperatures like 0° and fan speeds like 0 RPM.

giberg · 02-07-2010, 11:59 AM

If the bios controls the fan, why does the fan run differently if I work with Vista (usually I work only with Slackware)?

Anyway, I tried to recompile the kernel with the same config-generic-smp. I changed nothing (except built-in ext3 support).
Curiously it worked once (variable temperature, 45-50 C, variable fan speed...). No more.

. Now steadily 50 C and same speed. If I boot when cpu is cold, the fan works during POST only.

With Vista, cpu fan starts and stops regularly.

dmesg regarding "cooling device":

Code:

processor LNXCPU:00: registered as cooling_device0
processor LNXCPU:01: registered as cooling_device1
acpi device:39: registered as cooling_device2

Cathy344 · 02-07-2010, 07:43 PM

I'd like to request that lm_sensors in slackware64/ap/ be upgraded ASAP to version 3.1.2. It has the support for the AMD Fam10h temperature sensors that I need to make my machine (Toshi L555D-S7909 laptop) finally and completely supported by my OS.

giberg · 02-19-2010, 03:36 PM

Just an update:

often it works after hibernation...

Right now the fan stops and starts regularly and cpu temperature varies between 45 and 50 degrees.