From nobody Tue Dec 16 14:52:17 2025 Received: from mail-pl1-f201.google.com (mail-pl1-f201.google.com [209.85.214.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 87EAB30148D for ; Fri, 5 Dec 2025 23:19:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764976776; cv=none; b=YoBAO9gU9xjyLFr+ThiCwOVhB1xEaTrBPSr0Gy/LjCSS6rG+zZiTGdOUiMitPZHFeX414mzKYq5XYGgqutmWpngLzjI6pAqO0FgM/Najth9GLtAGK2eKSTxpJtuc+OSjVYH1jGjFU+x41MAHUrVBIHcOpVvg1lGMThLul7x/tc4= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764976776; c=relaxed/simple; bh=XbPk5Zu3tIL1j399oAQsxtB7EnPcWv++KAizvepSQe8=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=G+AXtYgEdBTVrWMlzffqK1JUn3U87amCl/IuswJAYubauPNSYgfHIZsf4nhX1zB7ia8rgynSE3ZBuU7XwC3tCZ6N25UYRt2iuzJ3kTLYUBjuz3i/f3i2Tjn/IT9G1l+dyn48fWrMojRa7DA7vmiC8hqad8XNXWnaWsmj86RxT1g= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=hq+ookEE; arc=none smtp.client-ip=209.85.214.201 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="hq+ookEE" Received: by mail-pl1-f201.google.com with SMTP id d9443c01a7336-29da1ea0b97so53066575ad.3 for ; Fri, 05 Dec 2025 15:19:34 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1764976772; x=1765581572; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:reply-to:from:to:cc:subject:date:message-id:reply-to; bh=lP72w5ANPVDKsXEE/wDJK3tXHkJNHOZxvL9A3UxnMuQ=; b=hq+ookEEOYL89/PbkmUhAMAMayac2mPlX7fXKvRwz3m59Ip3DVTFhj2pbN6W/88hJ5 MCZdyTxG5D9dA2Q2UlB50UUo93Q1xH8gfCIYwWadBa2p/3UHOe+wZfln9CHpOCk3z4nI 3AZTc/Ll1MqVKIcEUs/mMbWOpW8WFxkN/4AWeEKWztVTlUO+WX7qiryYYunWy3kZWq2+ BplS99JTomyhDV1OKFCOfNBBJw3hj1TBhJu0Uf0DNe/nUYwzSKWg+x00YE4VxE3Ow3xR xPuMp+yOIbNubU/zkVc5C+HJSeBUh6OKImTCGVMLME+E/QySPLYrCMqlcbQYAEnGlKzp J9Cg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1764976772; x=1765581572; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:reply-to:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=lP72w5ANPVDKsXEE/wDJK3tXHkJNHOZxvL9A3UxnMuQ=; b=e0dnUS1sfTsjA4CCwPIAdMSGoLJHZdhqMiEOhkISAucRzKefC55GFT7ErGtzjQ3Fq+ M/PXkuKT11jiGSpco99XPjOpWXfKHjLzB44HjQdqrmlflgo24BO9qm4QtWZTH+o5c008 9d/TF2H3Amm1R7j7OS8PfQjOxD5sN8afRy2aLGDSHHDur9bV76eNBPsFvZXt68nndhkw xnDVlAJzn4pBWHHId4liExkp7Js4A0ypmuow9393NEpo/RZE0J/fbvfYwbt1Xb5+pTqI g5vXaH/O/XlUIrnQmIfQaeHbqyssYRvgwRIt0WrKkVrzsMiEX+p8m77Gj9UtOSE4gmTV K65Q== X-Forwarded-Encrypted: i=1; AJvYcCXbVE6j9A/mZXLUacagqEeOvBCvqiRL6r/Guig0YOwcbaaiTrosuneav+4HZa6xtqelWZ/aARfK4zEDpZs=@vger.kernel.org X-Gm-Message-State: AOJu0YyuZI+sFPc6DwuK34zRmlzLhdk7t6pPeZ3QrQeEAjmS6ZSUzimZ hsQgnzIG8Ni3fJKVJfV5b+ak6ffpvcsLPHd3ZH1GuXsOgx1anvtVMf52SvkwAtOeXp4LGKLWP2C 4DfP/qg== X-Google-Smtp-Source: AGHT+IEcncbfzY4bTcbh3luKcr7xp+BgCYnZ3O4gVPcdWIBEayevCgcT/VujQOwDhDSxPh7S+ZSKPXOjFXg= X-Received: from plpo17.prod.google.com ([2002:a17:903:3e11:b0:29b:89b3:77b5]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a17:903:2f8c:b0:294:9813:4512 with SMTP id d9443c01a7336-29df5472d05mr5187925ad.3.1764976772004; Fri, 05 Dec 2025 15:19:32 -0800 (PST) Reply-To: Sean Christopherson Date: Fri, 5 Dec 2025 15:19:11 -0800 In-Reply-To: <20251205231913.441872-1-seanjc@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20251205231913.441872-1-seanjc@google.com> X-Mailer: git-send-email 2.52.0.223.gf5cc29aaa4-goog Message-ID: <20251205231913.441872-9-seanjc@google.com> Subject: [PATCH v3 08/10] KVM: nVMX: Switch to vmcs01 to update APIC page on-demand if L2 is active From: Sean Christopherson To: Sean Christopherson , Paolo Bonzini Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Dongli Zhang , Chao Gao Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" If the KVM-owned APIC-access page is migrated while L2 is running, temporarily load vmcs01 and immediately update APIC_ACCESS_ADDR instead of deferring the update until the next nested VM-Exit. Once changing the virtual APIC mode is converted to always do on-demand updates, all of the "defer until vmcs01 is active" logic will be gone. Signed-off-by: Sean Christopherson --- arch/x86/kvm/vmx/nested.c | 5 ----- arch/x86/kvm/vmx/vmx.c | 7 ++----- arch/x86/kvm/vmx/vmx.h | 1 - 3 files changed, 2 insertions(+), 11 deletions(-) diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c index 2b0702349aa1..8196a1ac22e1 100644 --- a/arch/x86/kvm/vmx/nested.c +++ b/arch/x86/kvm/vmx/nested.c @@ -5150,11 +5150,6 @@ void __nested_vmx_vmexit(struct kvm_vcpu *vcpu, u32 = vm_exit_reason, =20 nested_put_vmcs12_pages(vcpu); =20 - if (vmx->nested.reload_vmcs01_apic_access_page) { - vmx->nested.reload_vmcs01_apic_access_page =3D false; - kvm_make_request(KVM_REQ_APIC_PAGE_RELOAD, vcpu); - } - if ((vm_exit_reason !=3D -1) && (enable_shadow_vmcs || nested_vmx_is_evmptr12_valid(vmx))) vmx->nested.need_vmcs12_to_shadow_sync =3D true; diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 90e167f296d0..af8ec72e8ebf 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -6895,11 +6895,8 @@ void vmx_set_apic_access_page_addr(struct kvm_vcpu *= vcpu) kvm_pfn_t pfn; bool writable; =20 - /* Defer reload until vmcs01 is the current VMCS. */ - if (is_guest_mode(vcpu)) { - to_vmx(vcpu)->nested.reload_vmcs01_apic_access_page =3D true; - return; - } + /* Note, the VIRTUALIZE_APIC_ACCESSES check needs to query vmcs01. */ + guard(vmx_vmcs01)(vcpu); =20 if (!(secondary_exec_controls_get(to_vmx(vcpu)) & SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES)) diff --git a/arch/x86/kvm/vmx/vmx.h b/arch/x86/kvm/vmx/vmx.h index dfc9766a7fa3..078bc6fef7e6 100644 --- a/arch/x86/kvm/vmx/vmx.h +++ b/arch/x86/kvm/vmx/vmx.h @@ -132,7 +132,6 @@ struct nested_vmx { bool vmcs02_initialized; =20 bool change_vmcs01_virtual_apic_mode; - bool reload_vmcs01_apic_access_page; =20 /* * Enlightened VMCS has been enabled. It does not mean that L1 has to --=20 2.52.0.223.gf5cc29aaa4-goog