Re: [PATCH 12/43] KVM: nVMX: Add helpers to identify shadowed VMCS fields

From: Sean Christopherson
Date: Fri Jun 14 2019 - 12:15:42 EST


On Thu, Jun 13, 2019 at 07:02:58PM +0200, Paolo Bonzini wrote:
> diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
> index fc2b8f4cf45f..a6fe6cfe96f6 100644
> --- a/arch/x86/kvm/vmx/nested.c
> +++ b/arch/x86/kvm/vmx/nested.c
> @@ -4503,41 +4526,27 @@ static int handle_vmwrite(struct kvm_vcpu *vcpu)
> vmcs12_write_any(vmcs12, field, offset, field_value);
>
> /*
> - * Do not track vmcs12 dirty-state if in guest-mode
> - * as we actually dirty shadow vmcs12 instead of vmcs12.
> + * Do not track vmcs12 dirty-state if in guest-mode as we actually
> + * dirty shadow vmcs12 instead of vmcs12. Fields that can be updated
> + * by L1 without a vmexit are always updated in the vmcs02, i.e' don't

Minor typo (from my original patch), should be "i.e.", not "i.e'".

> + * "dirty" vmcs12, all others go down the prepare_vmcs02() slow path.
> */
> - if (!is_guest_mode(vcpu)) {
> - switch (field) {