Re: [lm-sensors] Could the k8temp driver be interfering with ACPI?

From: Pavel Machek
Date: Tue Mar 06 2007 - 16:21:37 EST


Hi!

> > > Is there anything preventing us from doing such a walk and pre-allocate
> > > all the I/O ranges? I am not familiar with the ACPI code at all, would
> > > you possibly propose a patch doing that?
> >
> > ACPI AML is probably turing-complete: I'm afraid you are trying to
> > solve the halting problem (-> impossible).
>
> Can you please translate this into something mere humans like myself
> have a chance to understand?

ACPI AML is turing-complete -- that means it is as powerful any
programming language. It can do arbitrary computation. That means it
is theoretically impossible to analyze its accesses using any program.

Now... may be possible to introduce _some_ ACPI BIOSes, but doing it
would certainly be very complex -- we are talking "put gcc into
kernel" here.

So no, it is not possible to preallocate the ranges.
Pavel
--
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/