# CPU0: local APIC error 0x40



## mickey (Aug 15, 2010)

Since upgrading from 8.0-RELEASE to 8.1-RELEASE, I keep seeing a lot of these messages in dmesg:


```
CPU0: local APIC error 0x40
```

Any hints to what might be the cause?


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## gcooper@ (Aug 17, 2010)

Do you run green_saver by chance?


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## mickey (Aug 17, 2010)

Indeed, saver is set to "green" in my /etc/rc.conf, although the machine runs under X most of the time.

The graphics adaptor is a GeForce 4 Ti, using the nvidia proprietary driver 96.43.18, if that is of any concern.


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## gcooper@ (Aug 23, 2010)

I can't find a reference to this value in the IA32/IA64 developer's manual, so it's definitely a bug but I'm not sure where it's coming from. The code that gets executed in the event of the error though is under 
	
	



```
lapic_handle_error
```
 (which is only called in amd64/amd64/apic_vector.S and i386/i386/apic_vector.s).

I would definitely talk to jhb@ about this, but in the time being you can set 'hint.apic.0.disabled' in loader.conf, or device.hints, or choose the appropriate entry in the beastie boot menu; this will kill off any MSI interrupts and some SMP functionality. Be sure to tell him what your CPU is and your motherboard.


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