Re: nmi is broken?

[Jan Kiszka <jan.kiszka@siemens.com>]

On 2011-05-03 15:31, Avi Kivity wrote:
> On 05/03/2011 01:37 PM, Jan Kiszka wrote:
>>>
>>>  Yes.  Unfortunately that is very vendor and model specific.  The
>>>  architectural PMU is supported, but that is only available on Intel.
>>
>> Is it supposed to have any practical value already? I did not yet find a
>> magic -cpu switch to let Linux detect anything, not to speak of perf or
>> watchdog support.
> 
> On the guest side it is supported for the watchdog 
> (arch/x86/kernel/cpu/perfctr-watchdog.c, look for 
> X86_FEATURE_ARCH_PERFMON).  It's also mentioned in perf_event_intel.c, 
> but I don't know if it will work without the other PMU features being 
> present.

I've tested with some SUSE 2.6.38 guest kernel, and it complained like
this:

(-cpu kvm64)
Performance Events: unsupported Netburst CPU model 6 no PMU driver, software events only.
NMI watchdog disabled (cpu0): hardware events not enabled

or
(-cpu host)
Performance Events: unsupported p6 CPU model 37 no PMU driver, software events only.
NMI watchdog disabled (cpu0): hardware events not enabled

Jan

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