Re: [PATCH v2 00/11] KVM in-guest performance monitoring

[David Ahern <daahern@cisco.com>]

On 06/14/2011 11:48 AM, David Ahern wrote:
> On 06/14/2011 11:33 AM, David Ahern wrote:
>> Avi: still no luck:
>> [    0.047996] Performance Events: unsupported p6 CPU model 0 no PMU
>> driver, software events only.
>>
>> qemu-kvm next branch, ce5f0a588b740e8f28f46a6009e12cfa72edc51f with your
>> perfmon cpuid change. Host and guest are both running your kvm next
>> branch with pmu patch series.
> 
> The perf init code is going down the !perfmon route:
> 
> 	if (!cpu_has(&boot_cpu_data, X86_FEATURE_ARCH_PERFMON)) {
> 		switch (boot_cpu_data.x86) {
> 		case 0x6:
> 			return p6_pmu_init();
> 		case 0xf:
> 			return p4_pmu_init();
> 		}
> 		return -ENODEV;
> 	}
> 
> Based on Patch 2 you are expecting the guest to have this feature set.
> I've tried +perfmon and +arch_perfmon in the cpu definition for qemu-kvm
> (e.g., -cpu host,model=0,+perfmon) no luck
> 
nevermind. I hand applied your qemu-kvm patch and changed ebx not eax. I
noticed  init_intel() looked at eax and discovered the user error.
Application of patch fixed and it works. :-)

David