Re: [PATCH v19 092/130] KVM: TDX: Implement interrupt injection

[Binbin Wu]

On 2/26/2024 4:26 PM, isaku.yamahata@xxxxxxxxx wrote:
> From: Isaku Yamahata<isaku.yamahata@xxxxxxxxx>
>
> TDX supports interrupt inject into vcpu with posted interrupt.  Wire up the
> corresponding kvm x86 operations to posted interrupt.  Move
> kvm_vcpu_trigger_posted_interrupt() from vmx.c to common.h to share the
> code.
>
> VMX can inject interrupt by setting interrupt information field,
> VM_ENTRY_INTR_INFO_FIELD, of VMCS.  TDX supports interrupt injection only
> by posted interrupt.  Ignore the execution path to access
> VM_ENTRY_INTR_INFO_FIELD.
>
> As cpu state is protected and apicv is enabled for the TDX guest, VMM can
> inject interrupt by updating posted interrupt descriptor.  Treat interrupt
> can be injected always.
>
> Signed-off-by: Isaku Yamahata<isaku.yamahata@xxxxxxxxx>
> Reviewed-by: Paolo Bonzini<pbonzini@xxxxxxxxxx>
> ---
>   arch/x86/kvm/vmx/common.h      | 71 ++++++++++++++++++++++++++
>   arch/x86/kvm/vmx/main.c        | 93 ++++++++++++++++++++++++++++++----
>   arch/x86/kvm/vmx/posted_intr.c |  2 +-
>   arch/x86/kvm/vmx/posted_intr.h |  2 +
>   arch/x86/kvm/vmx/tdx.c         | 25 +++++++++
>   arch/x86/kvm/vmx/vmx.c         | 67 +-----------------------
>   arch/x86/kvm/vmx/x86_ops.h     |  7 ++-
>   7 files changed, 190 insertions(+), 77 deletions(-)
[...]
>   
> +static void vt_set_interrupt_shadow(struct kvm_vcpu *vcpu, int mask)
> +{
> +	if (is_td_vcpu(vcpu))
> +		return;

Please add a blank line.

> +	vmx_set_interrupt_shadow(vcpu, mask);
> +}
> +
[...]
>   
> @@ -848,6 +853,12 @@ fastpath_t tdx_vcpu_run(struct kvm_vcpu *vcpu)
>   
>   	trace_kvm_entry(vcpu);
>   
> +	if (pi_test_on(&tdx->pi_desc)) {
> +		apic->send_IPI_self(POSTED_INTR_VECTOR);
> +
> +		kvm_wait_lapic_expire(vcpu);
As Chao pointed out, APIC timer change shouldn't be included in this patch.

Maybe better to put the splitted patch closer to patch
"KVM: x86: Assume timer IRQ was injected if APIC state is proteced"
becasue they are related.

> +	}
> +
>   	tdx_vcpu_enter_exit(tdx);
>   
>   	tdx_user_return_update_cache(vcpu);
> @@ -1213,6 +1224,16 @@ static int tdx_sept_remove_private_spte(struct kvm *kvm, gfn_t gfn,
>   	return tdx_sept_drop_private_spte(kvm, gfn, level, pfn);
>   }
>   
[...]