> On 15 Oct 2026, at 6:42 PM, Eric Auger <[email protected]> wrote:
> 
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> 
> Hi Khushit,
> 
> On 9/21/26 2:32 PM, Khushit Shah wrote:
>> Under KVM, the guest PMU is backed by the host PMU (event set, PMCR.N,
>> and PMCEID), which may not be portable across heterogeneous hosts.
>> 
>> Disable PMU support for named CPU models by clearing ARM_FEATURE_PMU in
>> the named-model init path so arm_cpu_post_init() does not create the
>> "pmu" property.
> 
> To me it shall be possible to turn PMU on even on named model. I
> understand it may create migration issues due to the HW adherence but yet.
> I think on x86 you can use -cpu Haswell-IBRS,pmu=on.
> 
Okay, fixed in v5.

Thanks,
Khushit

> Eric
> 
> 
>> 
>> Signed-off-by: Khushit Shah <[email protected]>
>> ---
>> target/arm/cpu-models.c | 4 ++++
>> 1 file changed, 4 insertions(+)
>> 
>> diff --git a/target/arm/cpu-models.c b/target/arm/cpu-models.c
>> index fed3197186..153ee10ae6 100644
>> --- a/target/arm/cpu-models.c
>> +++ b/target/arm/cpu-models.c
>> @@ -159,6 +159,10 @@ static void arm_named_cpu_initfn(Object *obj)
>>     /* 1.b Properly set RES1 fields. */
>>     reset_res1_fields(cpu);
>> 
>> +    /* Disable PMU for named CPU models. */
>> +    unset_feature(&cpu->env, ARM_FEATURE_PMU);
>> +    cpu->has_pmu = false;
>> +
>>     /* 2. Add sveNNNN and SYSREG_ properties */
>>     aarch64_add_sve_properties(obj);
>>     aarch64_add_idregs_properties(obj);
> 

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