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Re: [PATCH v4] KVM: VMX: Enable MSR-BASED TPR shadow even if APICv is inactive

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2016-09-22 07:43+0800, Wanpeng Li:
> From: Wanpeng Li <wanpeng.li@hotmail.com>
> 
> I observed that kvmvapic(to optimize flexpriority=N or AMD) is used 
> to boost TPR access when testing kvm-unit-test/eventinj.flat tpr case
> on my haswell desktop (w/ flexpriority, w/o APICv). Commit (8d14695f9542 
> x86, apicv: add virtual x2apic support) disable virtual x2apic mode 
> completely if w/o APICv, and the author also told me that windows guest
> can't enter into x2apic mode when he developed the APICv feature several 
> years ago. However, it is not truth currently, Interrupt Remapping and 
> vIOMMU is added to qemu and the developers from Intel test windows 8 can 
> work in x2apic mode w/ Interrupt Remapping enabled recently. 
> 
> This patch enables TPR shadow for virtual x2apic mode to boost 
> windows guest in x2apic mode even if w/o APICv.
> 
> Can pass the kvm-unit-test.
> 
> Suggested-by: Radim Krčmář <rkrcmar@redhat.com>
> Suggested-by: Wincy Van <fanwenyi0529@gmail.com>
> Reviewed-by: Radim Krčmář <rkrcmar@redhat.com>
> Cc: Paolo Bonzini <pbonzini@redhat.com>
> Cc: Radim Krčmář <rkrcmar@redhat.com>
> Cc: Wincy Van <fanwenyi0529@gmail.com>
> Cc: Yang Zhang <yang.zhang.wz@gmail.com>
> Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
> ---

Applied to kvm/queue, thanks.

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[PATCH v4] KVM: VMX: Enable MSR-BASED TPR shadow even if APICv is inactive Wanpeng Li <kernellwp@gmail.com> - 2016-09-22 01:50 +0200
  Re: [PATCH v4] KVM: VMX: Enable MSR-BASED TPR shadow even if APICv  is inactive Radim Krčmář <rkrcmar@redhat.com> - 2016-09-23 01:20 +0200

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