Comment 46 for bug 1290110

(In reply to Pohjoistuuli from comment #19)
> Hi!
>
> I have similar problem on HP ProBook 4510s (Firmware F.20, Intel T3000)
> running 64bit-kernel 3.13.9 (Kubuntu) or 64-bit kernel 3.13 - 3.14 on arch.
> I remarked that the regulation of the fan (not necessarily the fan itself!)
> stops after boot. So, if the system is cold, the fan is running at 0% (=
> off) or at 20% (which is an unusual number as the fan speed rises usually in
> 15% stepintel pentium dual core t3000 "microcode" updates on this hardware).
> On reboot, when the machine is warm, fan speeds of 30% or 45% are often
> observed depending on the CPU temperature at boot time. After booting, the
> fan speed does not change anymore and keeps constant. So, when the machine
> was started cold, the fan is off until the temperature reaches critical
> values and runs then with 90% (= full speed) until the temperature drops. It
> goes then off again completely.

I've seen exactly the same behavior on one of my test laptop.
And the problem is that ACPICA can not handle some kind of AML code well, PLUS, the fix for the problem ships in 3.13-rc1.
So the symptom I've seen is not a regression and exists in all Linux previous release.
Anyway, please attach the acpidump of your machine, so that I can check if they are the same AML problem.

BTW, it would be nice if you can try 3.12 kernel to verify if this is a regression or not.