From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B16EE34216C; Thu, 15 Jan 2026 17:34:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768498459; cv=none; b=XGe35LvJNvJDGswvak8y6HjiC25ylxW+GSWuAsrdEEQIMn3FiKWQ/rQqwqXRrZTOsVSXl9XJ3F8fy6h065pTJr/4HylqA8bMPPXBCufNTzWoesF53yRFzEmQrN8BZtTsTwKzXHhwVGTe0/fyYaYxd5nOxd6C+RQWS62VNOgmx2o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768498459; c=relaxed/simple; bh=6EGmBIUOZ7j8/1aAi7kLBi7RUXM2ITN2o7AUATFJ2wE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Ose10vO5EZ3wF03o4oNg0K6ACPADVs3/mT1+ihuKbxxk7Qm1uUeRgSySx8wdFeJBgUOTuAk6M7LtJpwj0TetkaO9tpI6WZGIj2iAF5C4fW3+dCXCnD3KL4aiQ+9lKsD4Pudg7n3cwKuTQs7fsOBTSo7QJ8HpxGWmzJoIdVSfvV0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=yU9OhOFe; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="yU9OhOFe" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3C40DC16AAE; Thu, 15 Jan 2026 17:34:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1768498459; bh=6EGmBIUOZ7j8/1aAi7kLBi7RUXM2ITN2o7AUATFJ2wE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=yU9OhOFeswFa51J3PUdK/WX7E0mT1HHH7g9P6KOB5cGRYhqX4iioIedlOtLcIKEVH g7Iy95P4QAFsVyiOP9mPYQk87pwWKYdiqIg9y42BKvrge+UFJk3Jd3mh44Rx11KwOH 77f/47snLIW2pCbxay0iPtHxPKZLx5BUG/EWlIvY= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Chao Gao , Dongli Zhang , Sean Christopherson , Sasha Levin Subject: [PATCH 5.15 439/554] KVM: nVMX: Immediately refresh APICv controls as needed on nested VM-Exit Date: Thu, 15 Jan 2026 17:48:25 +0100 Message-ID: <20260115164302.154897538@linuxfoundation.org> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20260115164246.225995385@linuxfoundation.org> References: <20260115164246.225995385@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Dongli Zhang [ Upstream commit 29763138830916f46daaa50e83e7f4f907a3236b ] If an APICv status updated was pended while L2 was active, immediately refresh vmcs01's controls instead of pending KVM_REQ_APICV_UPDATE as kvm_vcpu_update_apicv() only calls into vendor code if a change is necessary. E.g. if APICv is inhibited, and then activated while L2 is running: kvm_vcpu_update_apicv() | -> __kvm_vcpu_update_apicv() | -> apic->apicv_active = true | -> vmx_refresh_apicv_exec_ctrl() | -> vmx->nested.update_vmcs01_apicv_status = true | -> return Then L2 exits to L1: __nested_vmx_vmexit() | -> kvm_make_request(KVM_REQ_APICV_UPDATE) vcpu_enter_guest(): KVM_REQ_APICV_UPDATE -> kvm_vcpu_update_apicv() | -> __kvm_vcpu_update_apicv() | -> return // because if (apic->apicv_active == activate) Reported-by: Chao Gao Closes: https://lore.kernel.org/all/aQ2jmnN8wUYVEawF@intel.com Fixes: 7c69661e225c ("KVM: nVMX: Defer APICv updates while L2 is active until L1 is active") Cc: stable@vger.kernel.org Signed-off-by: Dongli Zhang [sean: write changelog] Link: https://patch.msgid.link/20251205231913.441872-3-seanjc@google.com Signed-off-by: Sean Christopherson [ exported vmx_refresh_apicv_exec_ctrl() and added declaration in vmx.h ] Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- arch/x86/kvm/vmx/nested.c | 2 +- arch/x86/kvm/vmx/vmx.c | 2 +- arch/x86/kvm/vmx/vmx.h | 1 + 3 files changed, 3 insertions(+), 2 deletions(-) --- a/arch/x86/kvm/vmx/nested.c +++ b/arch/x86/kvm/vmx/nested.c @@ -4684,7 +4684,7 @@ void nested_vmx_vmexit(struct kvm_vcpu * if (vmx->nested.update_vmcs01_apicv_status) { vmx->nested.update_vmcs01_apicv_status = false; - kvm_make_request(KVM_REQ_APICV_UPDATE, vcpu); + vmx_refresh_apicv_exec_ctrl(vcpu); } if ((vm_exit_reason != -1) && --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -4217,7 +4217,7 @@ static u32 vmx_vmexit_ctrl(void) ~(VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL | VM_EXIT_LOAD_IA32_EFER); } -static void vmx_refresh_apicv_exec_ctrl(struct kvm_vcpu *vcpu) +void vmx_refresh_apicv_exec_ctrl(struct kvm_vcpu *vcpu) { struct vcpu_vmx *vmx = to_vmx(vcpu); --- a/arch/x86/kvm/vmx/vmx.h +++ b/arch/x86/kvm/vmx/vmx.h @@ -386,6 +386,7 @@ void __vmx_set_segment(struct kvm_vcpu * u64 construct_eptp(struct kvm_vcpu *vcpu, hpa_t root_hpa, int root_level); bool vmx_guest_inject_ac(struct kvm_vcpu *vcpu); +void vmx_refresh_apicv_exec_ctrl(struct kvm_vcpu *vcpu); void vmx_update_exception_bitmap(struct kvm_vcpu *vcpu); bool vmx_nmi_blocked(struct kvm_vcpu *vcpu); bool __vmx_interrupt_blocked(struct kvm_vcpu *vcpu);