Re: [PATCH v19 117/130] KVM: TDX: Silently ignore INIT/SIPI

[Binbin Wu]

On 2/26/2024 4:26 PM, isaku.yamahata@xxxxxxxxx wrote:
> From: Isaku Yamahata <isaku.yamahata@xxxxxxxxx>
>
> The TDX module API doesn't provide API for VMM to inject INIT IPI and SIPI.
> Instead it defines the different protocols to boot application processors.
> Ignore INIT and SIPI events for the TDX guest.
>
> There are two options. 1) (silently) ignore INIT/SIPI request or 2) return
> error to guest TDs somehow.  Given that TDX guest is paravirtualized to
> boot AP, the option 1 is chosen for simplicity.
>
> Signed-off-by: Isaku Yamahata <isaku.yamahata@xxxxxxxxx>
> ---
[...]
> +
> +static void vt_vcpu_deliver_init(struct kvm_vcpu *vcpu)
> +{
> +	if (is_td_vcpu(vcpu)) {
> +		/* TDX doesn't support INIT.  Ignore INIT event */
> +		vcpu->arch.mp_state = KVM_MP_STATE_RUNNABLE;
Why change the mp_state to KVM_MP_STATE_RUNNABLE here?

And I am not sure whether we can say the INIT event is ignored since 
mp_state could be modified.

> +		return;
> +	}
> +
> +	kvm_vcpu_deliver_init(vcpu);
> +}
> +