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 8188C27465C for ; Wed, 31 Dec 2025 15:11:56 +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=1767193916; cv=none; b=P6sbW80vZo767YoqyZ2c46jrVfIFdNWSkllYSoTBSm3uQcSeOhU01gN1Vf+0+hTedue1l3N8J9dDD7z8juXtXXSDlx1fLWk3uutIRv/XaHAzD77mcRlhEFV7uDTRGncHK7Zg63bOj4Xgo17ufQahMZwoEikdlkvFfM/YXYlSXKI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767193916; c=relaxed/simple; bh=KUyO3/Dx2b1WTQLSnIwDw0B373hmWcExHQ8xJmFOkng=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=TgPtauKgg4e7Y8/BnfReB0PWu98rjyPV+6HfjJTFJJo6uuNo6f6QdCkSaVbDg1d8pzkrfPtfTxigqU3szKjpks2SHMUEOCJ4Aw5agJ353IoKIuWBCwloLW/Q+LPKUZHurQ9f4y4NpnvykASOimBjB+JaMfrViYC0tiKp8lF2vsU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=TbMZXJmD; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="TbMZXJmD" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 10A15C113D0; Wed, 31 Dec 2025 15:11:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1767193915; bh=KUyO3/Dx2b1WTQLSnIwDw0B373hmWcExHQ8xJmFOkng=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=TbMZXJmDVfXTOs8HHc+tBZCPjo0T6L7lJMLrs9v7h9h/l0wQ0/LcOTngwCqQNq1Mz Y1Y1wACL44zCHEMq2n3kR9tZl88uE1kobrDzpu5sKhuW5HKrAVOynre67efztnMAe3 XjQu150RBJQ/+Zj555N1tq6aCzsT1Yc3VXBw0LZddW+Ygg/YwYbJgLI/H/Qxf0SNBz uZdEvNBsEx2ovzQb+NB91TNYi8S38ZZ1BDqX4zFFPise5oFzta3QSCd52K4BuyHYfp SIxQdmEzGLmpkPYfP8F78GqYjO86FcppUDrGtOfWtMFg7kswVQ2cCYBKykVh3rcCA1 q0nbC5HXWskrA== From: Sasha Levin To: stable@vger.kernel.org Cc: Dongli Zhang , Chao Gao , Sean Christopherson , Sasha Levin Subject: [PATCH 6.1.y] KVM: nVMX: Immediately refresh APICv controls as needed on nested VM-Exit Date: Wed, 31 Dec 2025 10:11:53 -0500 Message-ID: <20251231151153.3146021-1-sashal@kernel.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <2025122926-gigabyte-rectangle-0c68@gregkh> References: <2025122926-gigabyte-rectangle-0c68@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 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 --- 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(-) diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c index 2c3cf4351c4c..bdc462944cb0 100644 --- a/arch/x86/kvm/vmx/nested.c +++ b/arch/x86/kvm/vmx/nested.c @@ -4847,7 +4847,7 @@ void nested_vmx_vmexit(struct kvm_vcpu *vcpu, u32 vm_exit_reason, 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 (vmx->nested.update_vmcs01_hwapic_isr) { diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 22e4c9bbbcb4..ebdc86030a7a 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -4387,7 +4387,7 @@ 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); diff --git a/arch/x86/kvm/vmx/vmx.h b/arch/x86/kvm/vmx/vmx.h index dc6f06326648..59c304dd51e6 100644 --- a/arch/x86/kvm/vmx/vmx.h +++ b/arch/x86/kvm/vmx/vmx.h @@ -408,6 +408,7 @@ void __vmx_set_segment(struct kvm_vcpu *vcpu, struct kvm_segment *var, int seg); 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); -- 2.51.0