Re: [PATCH v22 16/23] KVM: arm64: CCA: Add VCPU load/put for Realms

[Suzuki K Poulose <suzuki.poulose@arm.com>]

Hi Gavin

On 06/10/2026 04:16, Gavin Shan wrote:
> On 10/5/26 7:07 PM, Suzuki K Poulose wrote:
>> RMM controls the VCPU settings and most are hidden from the KVM, except
>> for the VGIC and timer bits.
>>
>> A later patch would add syncing the VCPU state into the Realm REC related
>> SMC parameters.

This is what you are looking for ^^^

>>
>> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
>> ---
>>   arch/arm64/kvm/arm.c | 18 ++++++++++++++++++
>>   1 file changed, 18 insertions(+)
>>
>> diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
>> index 6c81fec35ecec..294cea4cc8271 100644
>> --- a/arch/arm64/kvm/arm.c
>> +++ b/arch/arm64/kvm/arm.c
>> @@ -802,6 +802,13 @@ static void pkvm_vcpu_load(struct kvm_vcpu *vcpu)
>>                 &vcpu->arch.vgic_cpu.vgic_v3);
>>   }
>> +static void realm_vcpu_load(struct kvm_vcpu *vcpu)
>> +{
>> +    kvm_timer_vcpu_load(vcpu);
>> +    kvm_vgic_load(vcpu);
>> +    vcpu_set_wfx_traps(vcpu);
> 
> Why we need to call vcpu_set_wfx_traps(), which updates 'vcpu- 
>  >arch.hcr_el2'? I don't
> see how 'vcpu->arch.hcr_el2' is affects realm in RMM. Could you please 
> explain in the
> commit log.

See above.


Cheers
Suzuki

> 
>> +}
>> +
>>   void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
>>   {
>>       vcpu->cpu = cpu;
>> @@ -854,6 +861,12 @@ static void pkvm_vcpu_put(struct kvm_vcpu *vcpu)
>>       kvm_vcpu_pmu_restore_host(vcpu);
>>   }
>> +static void realm_vcpu_put(struct kvm_vcpu *vcpu)
>> +{
>> +    kvm_timer_vcpu_put(vcpu);
>> +    kvm_vgic_put(vcpu);
>> +}
>> +
>>   void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
>>   {
>>       vcpu->arch.vcpu_ops->vcpu_put(vcpu);
>> @@ -2213,6 +2226,11 @@ static const struct kvm_vcpu_ops pkvm_vcpu_ops = {
>>       .vcpu_put = pkvm_vcpu_put,
>>   };
>> +static const struct kvm_vcpu_ops realm_vcpu_ops = {
>> +    .vcpu_load = realm_vcpu_load,
>> +    .vcpu_put = realm_vcpu_put,
>> +};
>> +
>>   #define KVM_VCPU_OPS(flavor, ops)        \
>>       [(flavor)] = &(ops)
> 
> Thanks,
> Gavin
> 
>