From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chao Gao Subject: [PATCH v2] x86/kvm/vmx: Don't halt vcpu when L1 is injecting events to L2 Date: Fri, 9 Feb 2018 13:09:12 +0800 Message-ID: <1518152952-12633-1-git-send-email-chao.gao@intel.com> Cc: Chao Gao , linux-kernel@vger.kernel.org, x86@kernel.org, "H. Peter Anvin" , Ingo Molnar , Thomas Gleixner , =?UTF-8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= , Paolo Bonzini , Liran Alon To: kvm@vger.kernel.org Return-path: Received: from mga12.intel.com ([192.55.52.136]:9300 "EHLO mga12.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750770AbeBIFHj (ORCPT ); Fri, 9 Feb 2018 00:07:39 -0500 Sender: kvm-owner@vger.kernel.org List-ID: Although L2 is in halt state, it will be in the active state after VM entry if the VM entry is vectoring according to SDM 26.6.2 Activity State. Halting the vcpu here means the event won't be injected to L2 and this decision isn't reported to L1. Thus L0 drops an event that should be injected to L2. Cc: Liran Alon Signed-off-by: Chao Gao --- Changes in v2: - Remove VID stuff. Only handle event injection in this patch. --- arch/x86/kvm/vmx.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index bb5b488..42f39d9 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -10985,7 +10985,12 @@ static int nested_vmx_run(struct kvm_vcpu *vcpu, bool launch) if (ret) return ret; - if (vmcs12->guest_activity_state == GUEST_ACTIVITY_HLT) + /* + * If we're entering a halted L2 vcpu and the L2 vcpu won't be woken + * by event injection, halt vcpu for optimization. + */ + if ((vmcs12->guest_activity_state == GUEST_ACTIVITY_HLT) && + !(vmcs12->vm_entry_intr_info_field & VECTORING_INFO_VALID_MASK)) return kvm_vcpu_halt(vcpu); vmx->nested.nested_run_pending = 1; -- 1.9.1