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 36C712116F6; Tue, 17 Mar 2026 17:13:39 +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=1773767619; cv=none; b=OBHkJLzZjV3h+t569WWzxu9k7oTM9qDWpZsV+O4StQjQL/DmVHyxv/tGoGyrbXg6tYWEYsmcFxlO3tee9WU0Aq0YAnmO/+STvn4hrwVXqwODDQJ3ZnjhaxEK+ipigtss3NM9aAsM68LIIGq41TQJSP199AEQjogZuvXARl11vDY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773767619; c=relaxed/simple; bh=AQWAqGabsNhZY5ovI8XIzKdCWxnSu8H4krinDWdZwlg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=XCNZjJItzcuG2mPZ94Ei7GZR1SDGJ/EIbBWuErzhLd9uC+yHIVQt3BI7XuM0ll7zdZGkeHirIOPSOY/DvF/zNH4nYjar2i4lmtc5Vo7xDc3bpmBrD93DXWSxiOw2IzbVY4TjEGzs/PdjDxxpopzQwe6XKN300YmMEqUw7ZHhOlA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=E2E53gEl; 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="E2E53gEl" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 818D2C4CEF7; Tue, 17 Mar 2026 17:13:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1773767619; bh=AQWAqGabsNhZY5ovI8XIzKdCWxnSu8H4krinDWdZwlg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=E2E53gElgKjvBq1+VH6SgeVntV5XuFqlZCswGuENlmSIIQqObxgi364r+cSr4GGnl 6PziH1o9oMhlMvN/+KcQod28VaASTr/wL0pA5+8zqdupk20xJOepRM9KFJq3V7FIR7 euSTcrnD1nwxJk5f0SYnyIO+WSahAs8FwG7D4c2Q= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, "Naveen N Rao (AMD)" , Jim Mattson , Sean Christopherson , Paolo Bonzini Subject: [PATCH 6.18 124/333] KVM: SVM: Initialize AVIC VMCB fields if AVIC is enabled with in-kernel APIC Date: Tue, 17 Mar 2026 17:32:33 +0100 Message-ID: <20260317163003.963728962@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260317162959.345812316@linuxfoundation.org> References: <20260317162959.345812316@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 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Sean Christopherson commit 3989a6d036c8ec82c0de3614bed23a1dacd45de5 upstream. Initialize all per-vCPU AVIC control fields in the VMCB if AVIC is enabled in KVM and the VM has an in-kernel local APIC, i.e. if it's _possible_ the vCPU could activate AVIC at any point in its lifecycle. Configuring the VMCB if and only if AVIC is active "works" purely because of optimizations in kvm_create_lapic() to speculatively set apicv_active if AVIC is enabled *and* to defer updates until the first KVM_RUN. In quotes because KVM likely won't do the right thing if kvm_apicv_activated() is false, i.e. if a vCPU is created while APICv is inhibited at the VM level for whatever reason. E.g. if the inhibit is *removed* before KVM_REQ_APICV_UPDATE is handled in KVM_RUN, then __kvm_vcpu_update_apicv() will elide calls to vendor code due to seeing "apicv_active == activate". Cleaning up the initialization code will also allow fixing a bug where KVM incorrectly leaves CR8 interception enabled when AVIC is activated without creating a mess with respect to whether AVIC is activated or not. Cc: stable@vger.kernel.org Fixes: 67034bb9dd5e ("KVM: SVM: Add irqchip_split() checks before enabling AVIC") Fixes: 6c3e4422dd20 ("svm: Add support for dynamic APICv") Reviewed-by: Naveen N Rao (AMD) Reviewed-by: Jim Mattson Link: https://patch.msgid.link/20260203190711.458413-2-seanjc@google.com Signed-off-by: Sean Christopherson Signed-off-by: Paolo Bonzini Signed-off-by: Greg Kroah-Hartman --- arch/x86/kvm/svm/avic.c | 2 +- arch/x86/kvm/svm/svm.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) --- a/arch/x86/kvm/svm/avic.c +++ b/arch/x86/kvm/svm/avic.c @@ -321,7 +321,7 @@ void avic_init_vmcb(struct vcpu_svm *svm vmcb->control.avic_physical_id = __sme_set(__pa(kvm_svm->avic_physical_id_table)); vmcb->control.avic_vapic_bar = APIC_DEFAULT_PHYS_BASE; - if (kvm_apicv_activated(svm->vcpu.kvm)) + if (kvm_vcpu_apicv_active(&svm->vcpu)) avic_activate_vmcb(svm); else avic_deactivate_vmcb(svm); --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -1141,7 +1141,7 @@ static void init_vmcb(struct kvm_vcpu *v svm_clr_intercept(svm, INTERCEPT_PAUSE); } - if (kvm_vcpu_apicv_active(vcpu)) + if (enable_apicv && irqchip_in_kernel(vcpu->kvm)) avic_init_vmcb(svm, vmcb); if (vnmi)