Re: Tell user when ACPI is killing machine

Pavel Machek
2003-11-28T23:43:02Z

Hi!

> > On critical overheat (or perceived critical overheat -- acpi bioses on
> > some notebooks apparently report bogus values from time to time),
> > kernel itself calls /sbin/halt *without telling anything*. User can
> > not see anything, his machine just shuts down cleanly. Bad.
>
> Sorry if this is a bit OT, but why doesn't ACPI scale the CPU

Yep it is OT.

> frequency back instead of shutting down? This is what APM does on my
> laptop (presumably in the BIOS) but when I enable ACPI the machine
> shuts down whenever I do something CPU intensive (yes; it's a poorly
> designed laptop). I have cpufreq support (cpufreq: P4/Xeon(TM) CPU
> On-Demand Clock Modulation available). Has this kind of thing been

It should try scaling first (and it works for me (tm)), but when
temperature reaches "critical" limit it is assumed that everything
failed and shutdown is only option. (On hp omnibook even in slowest
possible mode, if you play .mpg video it overheats.)

> added since I last tried it, or do I actually have to actively set up
> cpufreq in user space to get thermally-induced clock modulation? Or is
> not even possible with the current state of things?

cpufreq is not connected to acpi thermal subsystem. Dominik has some
patches to change that, IIRC.
Pavel

--
When do you have a heart between your knees?
[Johanka's followup: and *two* hearts?]