Re: [PATCH] KVM: vmx: expose more information for KVM_INTERNAL_ERROR_DELIVERY_EV exits

From: David Hildenbrand
Date: Wed Jul 05 2017 - 08:25:20 EST


On 05.07.2017 12:38, Paolo Bonzini wrote:
> This exit ended up being reported, but the currently exposed data does not provide
> much of a starting point for debugging. In the reported case, the vmexit was
> an EPT misconfiguration (MMIO access). Let userspace report ethe exit qualification
> and, if relevant, the GPA.
>
> Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
> ---
> arch/x86/kvm/vmx.c | 8 +++++++-
> 1 file changed, 7 insertions(+), 1 deletion(-)
>
> diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
> index 6dcc4873e435..4be80c3ac24d 100644
> --- a/arch/x86/kvm/vmx.c
> +++ b/arch/x86/kvm/vmx.c
> @@ -8408,9 +8408,15 @@ static int vmx_handle_exit(struct kvm_vcpu *vcpu)
> exit_reason != EXIT_REASON_TASK_SWITCH)) {
> vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
> vcpu->run->internal.suberror = KVM_INTERNAL_ERROR_DELIVERY_EV;
> - vcpu->run->internal.ndata = 2;
> + vcpu->run->internal.ndata = 3;
> vcpu->run->internal.data[0] = vectoring_info;
> vcpu->run->internal.data[1] = exit_reason;
> + vcpu->run->internal.data[2] = vcpu->arch.exit_qualification;
> + if (exit_reason == EXIT_REASON_EPT_MISCONFIG) {
> + vcpu->run->internal.ndata++;
> + vcpu->run->internal.data[3] =
> + vmcs_read64(GUEST_PHYSICAL_ADDRESS);

vcpu->run->internal.data[vcpu->run->internal.ndata++] = ...

So we don't have to name the position explicitly.

Whatever you prefer.

Reviewed-by: David Hildenbrand <david@xxxxxxxxxx>

> + }
> return 0;
> }
>
>


--

Thanks,

David