Re: [PATCH v1 13/23] KVM: VMX: Handle VMX nested exception for FRED

Chao Gao
2023-11-14T07:40:26Z

> /* Require Write-Back (WB) memory type for VMCS accesses. */
>@@ -7313,11 +7328,12 @@ static void __vmx_complete_interrupts(struct kvm_vcpu *vcpu,
> }
> }
>
>- if (idt_vectoring_info & VECTORING_INFO_DELIVER_CODE_MASK) {
>- u32 err = vmcs_read32(error_code_field);
>- kvm_requeue_exception_e(vcpu, vector, err);
>- } else
>- kvm_requeue_exception(vcpu, vector);
>+ if (idt_vectoring_info & VECTORING_INFO_DELIVER_CODE_MASK)
>+ kvm_requeue_exception_e(vcpu, vector, vmcs_read32(error_code_field),
>+ idt_vectoring_info & INTR_INFO_NESTED_EXCEPTION_MASK);
>+ else
>+ kvm_requeue_exception(vcpu, vector,
>+ idt_vectoring_info & INTR_INFO_NESTED_EXCEPTION_MASK);

Exiting-event identification can also have bit 13 set, indicating a nested
exception encountered and caused VM-exit. when reinjecting the exception to
guests, kvm needs to set the "nested" bit, right? I suspect some changes
to e.g., handle_exception_nmi() are needed.