Re: [v3.20]: Missing /sys/class/ACAD directory OR Cannot release Mutex

From: Rafael J. Wysocki
Date: Mon Feb 23 2015 - 18:00:58 EST

On Sunday, February 22, 2015 01:33:09 PM JÃrg Otte wrote:
> Starting with kernel 3.19.0-05184-g18320f2, I often find my notebook
> running with 'powersave' policy even if it is on AC.
> It turned out that /sys/class/ACAD directory is missing and in the
> logs I see:
> ACPI Error: Cannot release Mutex [MUT0], not acquired (20150204/exmutex-376)
> ACPI Error: Method parse/execution failed [\_SB_.ACAD._PSR] (Node
> ffff880216028d48), AE_AML_MUTEX_NOT_ACQUIRED (20150204/psparse-536)
> ACPI Exception: AE_AML_MUTEX_NOT_ACQUIRED, Error reading AC Adapter
> state (20150204/ac-131)
> At the last 25 startups since 3.19.0-05184-g18320f2 it occured 13 times.
> It does not occur with kernels older than 3.19.0-05184-g18320f2.

Which mainline commit is that?

The only changes in 4.0-rc1 that can affect that are the ACPI EC updates IIRC.

Is there a chance to try the acpi-ec branch from linux-pm.git and see if the
problem is there?


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