On Thu, 28 Jun 2012 12:15:43 +0100, Michael Zintakis wrote:

quoted

That's the *good* outcome. The bad outcome involves these register 
accesses racing in a way that disables fan control or thermal trip 
points and risks causing hardware damage. It's not safe for two 
different codepaths to access the same hardware without having any kind 
of locking, so if your system firmware declares that ACPI is using the 
temperature device the hardware sensors framework will refuse to.

All noted, thanks for the explanation - pretty hairy stuff! The tragic 
thing is, I have no way of telling ACPI to *not* use or "implement" its 
own fan, voltage, temperature management and let a more capable piece of 
software (the f71882fg driver in this case) do that job!

This has been my very claim for several years now. My next step is to
find someone involved in the ACPI specification that would be willing
to discuss the problem with me and implement a solution in the next
ACPI specification.

Don't hold your breath though, it will take years before the problem
actually gets solved for the end user - if that ever happens.

-- 
Jean Delvare