Re: [PATCH v4 03/21] KVM: arm64: Support SDEI_VERSION hypercall

Gavin Shan
2022-01-11T09:25:27Z

Hi Eric,

On 11/9/21 11:26 PM, Eric Auger wrote:
> On 8/15/21 2:13 AM, Gavin Shan wrote:
>> This supports SDEI_VERSION hypercall by returning v1.0.0 simply
> s/This supports/Add Support. I think this is the prefered way to start
> the commit msg. Here and elsewhere.

Ok.

>> when the functionality is supported on the VM and vCPU.
> Can you explain when the functionality isn't supported on either. From
> the infra patch I have the impression that an allocation failure is the
> sole cause of lack of support?

Yes, it's the only reason that SDEI isn't supported. I will
mention this in the commit log in next respin.

>>
>> Signed-off-by: Gavin Shan <gshan@redhat.com>
>> ---
>> arch/arm64/kvm/sdei.c | 18 ++++++++++++++++++
>> 1 file changed, 18 insertions(+)
>>
>> diff --git a/arch/arm64/kvm/sdei.c b/arch/arm64/kvm/sdei.c
>> index ab330b74a965..aa9485f076a9 100644
>> --- a/arch/arm64/kvm/sdei.c
>> +++ b/arch/arm64/kvm/sdei.c
>> @@ -70,6 +70,22 @@ static void kvm_sdei_remove_vcpu_events(struct kvm_vcpu *vcpu)
>> }
>> }
>>
>> +static unsigned long kvm_sdei_hypercall_version(struct kvm_vcpu *vcpu)
>> +{
>> + struct kvm *kvm = vcpu->kvm;
>> + struct kvm_sdei_kvm *ksdei = kvm->arch.sdei;
>> + struct kvm_sdei_vcpu *vsdei = vcpu->arch.sdei;
>> + unsigned long ret = SDEI_NOT_SUPPORTED;
> nit: I would remove ret local variable

Ok.

>> +
>> + if (!(ksdei && vsdei))
>> + return ret;
>> +
>> + /* v1.0.0 */
>> + ret = (1UL << SDEI_VERSION_MAJOR_SHIFT);
>> +
>> + return ret;
>> +}
>> +
>> int kvm_sdei_hypercall(struct kvm_vcpu *vcpu)
>> {
>> u32 func = smccc_get_function(vcpu);
>> @@ -78,6 +94,8 @@ int kvm_sdei_hypercall(struct kvm_vcpu *vcpu)
>>
>> switch (func) {
>> case SDEI_1_0_FN_SDEI_VERSION:
>> + ret = kvm_sdei_hypercall_version(vcpu);
>> + break;
>> case SDEI_1_0_FN_SDEI_EVENT_REGISTER:
>> case SDEI_1_0_FN_SDEI_EVENT_ENABLE:
>> case SDEI_1_0_FN_SDEI_EVENT_DISABLE:
>>

Thanks,
Gavin