Re: [PATCH v5 11/13] hvf: gate ARM_FEATURE_PMU register emulation behind not being at EL2

["Philippe Mathieu-Daudé" <philmd@linaro.org>]

On 28/7/25 15:41, Mohamed Mediouni wrote:
>  From Apple documentation:
> 
>> When EL2 is disabled, PMU register accesses trigger "Trapped MSR, MRS, or
>> System Instruction" exceptions. When this happens, hv_vcpu_run() returns, and the
>>  hv_vcpu_exit_t object contains the information about this exception.
> 
>> When EL2 is enabled, the handling of PMU register accesses is determined by the PMUVer
>> field of ID_AA64DFR0_EL1 register.
>> If the PMUVer field value is zero or is invalid, PMU register accesses generate "Undefined"
>> exceptions, which are sent to the guest.
>> If the PMUVer field value is non-zero and valid, PMU register accesses are emulated by the framework.
>> The ID_AA64DFR0_EL1 register can be modified via hv_vcpu_set_sys_reg API.
> 
> Signed-off-by: Mohamed Mediouni <mohamed@unpredictable.fr>
> ---
>   target/arm/hvf/hvf.c | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Tested-by: Philippe Mathieu-Daudé <philmd@linaro.org>