Re: [PATCH v3 05/10] KVM: nVMX: Switch to vmcs01 to update TPR threshold on-demand if L2 is active

[Chao Gao]

On Fri, Dec 05, 2025 at 03:19:08PM -0800, Sean Christopherson wrote:
>If KVM updates L1's TPR Threshold while L2 is active, temporarily load
>vmcs01 and immediately update TPR_THRESHOLD instead of deferring the
>update until the next nested VM-Exit.  Deferring the TPR Threshold update
>is relatively straightforward, but for several APICv related updates,
>deferring updates creates ordering and state consistency problems, e.g.
>KVM at-large thinks APICv is enabled, but vmcs01 is still running with
>stale (and effectively unknown) state.
>
>Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>

Reviewed-by: Chao Gao <chao.gao@xxxxxxxxx>