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

[Gavin Shan]

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@xxxxxxxxxx>
> > ---
> >   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