local APIC error 0x40

[Dan Allen]

Running FreeBSD 8.3 -- and updating sources on a daily base and building everything -- I found a new APIC/ACPI problem introduced in the past week.

I have a Toshiba Satellite U205 with an Intel Core Duo (not a Core 2).  It used to work fine with both cores but then sometime in on the road to BSD 8.0 the machine began hanging.  So I added to /boot/loader.conf

  hint.apic.0.disabled="1"

and the machine only had one core but it went back to being reliable.

The laptop sits idle a lot, so I also have in /etc/rc.conf

  performance_cx_lowest="LOW"

and the fans stay off unless I am doing a build.  Everything was good.

I went away on a trip last week for five days, came home, did a csup to RELENG_8 and rebuilt the world, as usual, and now the fans are always running full!

If I comment out hint.apic.0.disabled="1" from /boot/loader.conf and reboot, the results are a mixed bag:

1) I get my 2nd core back, and it no longer hangs! Hurray.
2) The fans go back to usually being off and silent.  Hurray!
3) I get zillions of error messages streaming saying:

  CPU0: local APIC error 0x40
  CPU1: local APIC error 0x40

No good!


I am sitting at a prompt, no X-Windows, no apps running (other than the usual demons), and every few seconds I get another pair of these error messages.

4) The error appears benign other than flooding the console.  Everything works, nothing hangs, I can build the OS and everything appears fine.

So how do I get rid of these messages?  What does error 0x40 mean?

Thanks,

Dan Allen