Re: [PATCH v19 120/130] KVM: TDX: Add a method to ignore dirty logging

Edgecombe, Rick P
2024-03-15T00:06:41Z

On Mon, 2024-02-26 at 00:27 -0800, isaku.yamahata@intel.com wrote:
>
> +static void vt_update_cpu_dirty_logging(struct kvm_vcpu *vcpu)
> +{
> +       if (KVM_BUG_ON(is_td_vcpu(vcpu), vcpu->kvm))
> +               return;
> +
> +       vmx_update_cpu_dirty_logging(vcpu);
> +}

Discussed this first part offline, but logging it here. Since
guest_memfd cannot have dirty logging, this is essentially bugging the
VM if somehow they manage anyway. But it should be blocked via the code
in check_memory_region_flags().

On the subject of warnings and KVM_BUG_ON(), my feeling so far is that
this series is quite aggressive about these. Is it due the complexity
of the series? I think maybe we can remove some of the simple ones, but
not sure if there was already some discussion on what level is
appropriate.