From nobody Sun Feb 8 22:58:26 2026 Received: from mail-pl1-f202.google.com (mail-pl1-f202.google.com [209.85.214.202]) (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 F1C273033F8 for ; Fri, 9 Jan 2026 03:45:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.202 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767930347; cv=none; b=u3LIXllyfwyGHxOzV1uzYS8nhfl51E9/oEVCWY+peQOeu3F39hLNCKQaBIQK0zNh9rqSj34swo44GtN9qRGOk3A1EK2K+KDSZ73hc09KPbHymya2AqeAm2vE8NJV1H4y4gD6jJfG0GLHd15LRH8o+EBvcmUXRi/kEKMyQHztkmI= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767930347; c=relaxed/simple; bh=o1kKEv4y9G1l1AcUONDgAB0YJoa373EmyRiTlcErh/0=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=QgGYy5I81ZE9hUY74pbtavDWzH//vtVa9QMv3btBvs0wbHvrkVWBtu0+C6PtCp3IJZ1t5XCqvd0ueNETjQyRfr0rI1HYsAMPM8HV67A8Ak4wEVGW1yczWpwG0BSRKT3I8XXdCQoWQnSC5xLODBHoc8mqFKgZF2AP+F3WeL05f/U= 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=jdftKX3b; arc=none smtp.client-ip=209.85.214.202 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="jdftKX3b" Received: by mail-pl1-f202.google.com with SMTP id d9443c01a7336-2a13be531b2so46593975ad.2 for ; Thu, 08 Jan 2026 19:45:45 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1767930345; x=1768535145; 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=J6s9SI/r2bnHM1n7Bm/zP7cWS7ymjW9gwaRGx74RRrI=; b=jdftKX3bPcP9Aatvy4S9m/0nOLlmJdi2RpXf3cqmBcpW121DWJLyiTgemnK//zuap9 n10G6Lm+2FzzDUolhbvaPDApabreY+iwz5YfOnu5RngS2m7DzQO4vRPNSegcRr5vB4b5 fNhbI155U3HP8VUmliScSlcEwW+v2J0v4Cu+VvmHHu8qx9qfmruVWUyTsYJEu9DWRklV CwIsUP221js2c80ejPdIudPiLiQBujFwtzXS/UP6AAkEcXze+qPORyDImQEaRIByefq2 9M6uuWhsoCXy++syUN7I7B67GKOT/6j62C9Zj8zEcEQeL/U1cSPyRToLYQ8nCHO47biL d6jQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1767930345; x=1768535145; 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=J6s9SI/r2bnHM1n7Bm/zP7cWS7ymjW9gwaRGx74RRrI=; b=Df+sYWMTR/K/CfY0SbgTCBCWYErAp5TJQqBDnD7f4m2d6DLVvwpjJLsTmUsOR8Ifk8 ni/50g9omvltJPQM2Cy2GkT460xvceZUWNcgtU1Fvd1hr5Z3M8VSTLaCEmw3GSPa0dUM KTORIuZddAdqvQ5mF0m3ow/uJGKJhp9+CTEhnmBiF6GMmR6MYYD7AUh0hr5PlHvlMDq7 /ItmWnw9NASv4ihpHMiM5c6pnMzfd792UzRB9YrHQmMiHDOZaOZdjieTguZIB65/aEZB bc0J/UKo9NlKYBFflHbD9GUkYz1HwVoOdEX6WzfoM0z3sYnjjq04ez6VFklVrwKVfXlX e9zA== X-Forwarded-Encrypted: i=1; AJvYcCUtvdh4PNK/I0MqebZraVFlV6fJ5hzvzhEpRtg96aElKowMZjkmOP1jRKIXr2JlR1FnFXrBWpRRM6U7zC4=@vger.kernel.org X-Gm-Message-State: AOJu0Yy9CxpqmubIqoRqDifiP0WQ9XiZ72c+7u0K3HRpGVc9Z/zL5oNt /97HwB8+oL4t3k9ejK6GEr7yHCWRyPTlqhl+bQdv4LCsFtmjdweESvGJ9yNpYhdbnKJUaRlmQD6 gKlT5MQ== X-Google-Smtp-Source: AGHT+IGOKgPXbL3Nx4d+n28wqdscdI7eBJGYNqyaTNz7Nh7KHW8RUVrTgLfwaO8PWz8RoWeT5QsLFUa2oZs= X-Received: from plkn7.prod.google.com ([2002:a17:902:6a87:b0:2a1:4291:bc8e]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a17:903:40c9:b0:298:3aa6:c03d with SMTP id d9443c01a7336-2a3ee51bdd6mr87464325ad.57.1767930345433; Thu, 08 Jan 2026 19:45:45 -0800 (PST) Reply-To: Sean Christopherson Date: Thu, 8 Jan 2026 19:45:30 -0800 In-Reply-To: <20260109034532.1012993-1-seanjc@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260109034532.1012993-1-seanjc@google.com> X-Mailer: git-send-email 2.52.0.457.g6b5491de43-goog Message-ID: <20260109034532.1012993-7-seanjc@google.com> Subject: [PATCH v4 6/8] 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, 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. Reviewed-by: Chao Gao 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 2.52.0.457.g6b5491de43-goog