ACPI Thermal Zones and unwanted reset of Trip Points

[Olaf Conradi <oohlaf@gmail.com>]

Hello,

I'm running Debian Unstable on my laptop and have a question about
trip points in ACPI thermal zones.

My laptop gets too hot when I compile a kernel, or in font generation
during installation of a latex font. This causes the laptop to
shutdown.

On my laptop (Asus L8400K) the trip points are:

# cat /proc/acpi/thermal_zone/THRM/trip_points
critical (S5):           80 C
passive:                 70 C: tc1=1 tc2=4 tsp=300 devices=0xc127cb60
active[0]:               60 C: devices=0xc127b800

When I set them to:

# echo -n "80:0:60:55:0" > /proc/acpi/thermal_zone/THRM/trip_points
# cat /proc/acpi/thermal_zone/THRM/trip_points
critical (S5):           80 C
passive:                 60 C: tc1=1 tc2=4 tsp=300 devices=0xc127cb60
active[0]:               55 C: devices=0xc127b800

I get much better results and it rarely overheats.

But, for some reason, the trip points get reset every now and then
(usually within 30 mintes or so, don't know the exact interval).

Does anyone know what causes the trip point setting to be reset?

I'm using debian kernel 2.6.14 with udev from unstable.


Thanks,
Olaf