Re: [PATCH] KVM: nVMX: remove unnecessary vmwrite from L2->L1 vmexit

From: Jim Mattson
Date: Mon Jan 01 2018 - 19:45:38 EST


Reviewed-by: Jim Mattson <jmattson@xxxxxxxxxx>

On Mon, Jan 1, 2018 at 2:58 PM, Paolo Bonzini <pbonzini@xxxxxxxxxx> wrote:
> The POSTED_INTR_NV field is constant (though it differs between the vmcs01 and
> vmcs02), there is no need to reload it on vmexit to L1.
>
> Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
> ---
> arch/x86/kvm/vmx.c | 3 ---
> 1 file changed, 3 deletions(-)
>
> diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
> index e6223fe8faa1..1e184830a295 100644
> --- a/arch/x86/kvm/vmx.c
> +++ b/arch/x86/kvm/vmx.c
> @@ -11610,9 +11610,6 @@ static void load_vmcs12_host_state(struct kvm_vcpu *vcpu,
> */
> vmx_flush_tlb(vcpu, true);
> }
> - /* Restore posted intr vector. */
> - if (nested_cpu_has_posted_intr(vmcs12))
> - vmcs_write16(POSTED_INTR_NV, POSTED_INTR_VECTOR);
>
> vmcs_write32(GUEST_SYSENTER_CS, vmcs12->host_ia32_sysenter_cs);
> vmcs_writel(GUEST_SYSENTER_ESP, vmcs12->host_ia32_sysenter_esp);
> --
> 1.8.3.1
>