Re: [lm-sensors] Could the k8temp driver be interfering with ACPI?
From: Jean Delvare <hidden>
Date: 2007-02-21 15:07:46
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Hi Matthew, On Tue, 20 Feb 2007 15:18:13 +0000, Matthew Garrett wrote:
On Sun, Feb 18, 2007 at 06:38:05PM +0100, Jean Delvare wrote:quoted
ACPI is broken here, not k8temp, so let's fix ACPI instead. ACPI doesn't conflict with only k8temp, but with virtually all hardware monitoring drivers, all I2C/SMBus drivers, and probably other types of drivers too. We just can't restrict or blacklist all these drivers because ACPI misbehaves.No, the simple fact of the matter is that if you're running on an ACPI platform you need to change some of your assumptions. ACPI owns the hardware. The OS doesn't. To an extent this has always been true on
The Linux device driver model assumes that it owns the hardware. If this is not true, then should we prevent any non-ACPI driver from loading as soon as ACPI is enabled?
laptops and servers /anyway/ - the BIOS is free to have a wide variety of SMM insanity that invalidates basic assumptions like "If I hold this lock, nothing can interrupt me between this write and this read". That's simply not true.
Yeah, this is correct, and just as unfortunate. It's amazingly sad that hardware vendors as a whole are still repeating the same design mistakes over and over again :(
So this isn't about fixing ACPI. It's about trying to find a mechanism that allows ACPI and raw hardware drivers to coexist, which is made
Exactly what I said, you're only rewording it to make it sound nicer ;)
somewhat harder by it not being a situation that the platform designers have considered in the slightest. The suggested low-level driver for io-port arbitration would certainly be a step forward in making this work better.
I sure hope we can find a solution, by as your said yourself, nothing is going to prevent SMM and similar oddities from messing up the drivers assumptions. -- Jean Delvare