Re: [lm-sensors] Fintek f71882fg ACPI conflict
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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!Could any of the more knowledgeable on here explain why is it such a bad idea please?Because there's no handshaking between the firmware and the OS driver, and accesses to hardware sensors are often indexed. Imagine this scenario:ACPI lmsensors ---- --------- select temperature register select fan speed register read value read valueACPi will read the fan speed register instead of the temperature register, and the value may be far too high and cause a critical shutdown of the system.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.
What is the alternative? There is none that I could see. I tried using memmap to force ACPI not to use the memory region claimed by f71882fg (0x290 - 8 bytes long according to the driver), but that didn't help much. What am I supposed to do - deactivate ACPI completely? That would be like going after a fly with a bazooka!
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