Atom N270 - ACPI Error: [RTMP] Namespace lookup failure

[Andriy Gapon]

on 14/07/2011 18:31 Ed VanderPloeg said the following:
> Could the system overheat, or get incorrectly shut down when acpi fails to get the
> current temperature?

I am not sure.  There is no explicit error handling in acpi thermal driver,
tz_temperature would probably always stay at zero (Kelvin) and it's not clear what
the driver ends up doing in this case.  You can probably simply observe your
troublesome system and see which ACx state is used and how fast your fan rotates.

> What is the best way to work around this problem?  Setting a very high polling
> rate or disabling it inside loader.conf:

Interval, not rate.

> debug.acpi.disable="thermal"

This means that fan speed will stay whatever it was at boot time.  And there won't
be any passive cooling via CPU throttling.

> In 2008 Kevin Foo thought it might not be safe to disable it:
> 
> http://unix.derkeiler.com/Mailing-Lists/FreeBSD/current/2008-01/msg00791.html

There is no justification, only an opinion in that post.
You can decide and/or try for yourself.

> Or do I need to boot with ACPI disabled until a BIOS fix is available?

You can try this, but I am not sure if your system would even boot successfully.
A lot of modern HW just plain doesn't work without ACPI.

> On 2011-07-04 1:55 AM, Andriy Gapon wrote:
>> on 02/07/2011 05:16 Ed VanderPloeg said the following:
>>>
>>> # egrep '(^| )est' dmesg.8-release
>>> est0:<Enhanced SpeedStep Frequency Control>  on cpu0
>>> est: CPU supports Enhanced Speedstep, but is not recognized.
>>> est: cpu_vendor GenuineIntel, msr 60f0c270600060f
>>> device_attach: est0 attach returned 6
>>> est1:<Enhanced SpeedStep Frequency Control>  on cpu1
>>> est: CPU supports Enhanced Speedstep, but is not recognized.
>>> est: cpu_vendor GenuineIntel, msr 60f0c270600060f
>>> device_attach: est1 attach returned 6
>>>
>>> # egrep '(^| )est' dmesg.8-stable
>>> est0:<Enhanced SpeedStep Frequency Control>  on cpu0
>>> est1:<Enhanced SpeedStep Frequency Control>  on cpu1
>>
>> So this was improved.  Thanks!
>>


-- 
Andriy Gapon