From patchwork Fri Jul 2 22:04:36 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Isaku Yamahata X-Patchwork-Id: 12356627 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id EA0DFC07E95 for ; Fri, 2 Jul 2021 22:05:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D7BB96142B for ; Fri, 2 Jul 2021 22:05:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233479AbhGBWIP (ORCPT ); Fri, 2 Jul 2021 18:08:15 -0400 Received: from mga12.intel.com ([192.55.52.136]:50197 "EHLO mga12.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233159AbhGBWH6 (ORCPT ); Fri, 2 Jul 2021 18:07:58 -0400 X-IronPort-AV: E=McAfee;i="6200,9189,10033"; a="188472736" X-IronPort-AV: E=Sophos;i="5.83,320,1616482800"; d="scan'208";a="188472736" Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by fmsmga106.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Jul 2021 15:05:24 -0700 X-IronPort-AV: E=Sophos;i="5.83,320,1616482800"; d="scan'208";a="642814770" Received: from ls.sc.intel.com (HELO localhost) ([143.183.96.54]) by fmsmga006-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Jul 2021 15:05:24 -0700 From: isaku.yamahata@intel.com To: Thomas Gleixner , Ingo Molnar , Borislav Petkov , "H . Peter Anvin" , Paolo Bonzini , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , erdemaktas@google.com, Connor Kuehl , Sean Christopherson , x86@kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org Cc: isaku.yamahata@intel.com, isaku.yamahata@gmail.com, Kai Huang , Sean Christopherson Subject: [RFC PATCH v2 30/69] KVM: x86: Add per-VM flag to disable in-kernel I/O APIC and level routes Date: Fri, 2 Jul 2021 15:04:36 -0700 Message-Id: <2ee64e43e06ba3f6b9d0f90a53ca820f77a47792.1625186503.git.isaku.yamahata@intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Kai Huang Add a flag to let TDX disallow the in-kernel I/O APIC, level triggered routes for a userspace I/O APIC, and anything else that relies on being able to intercept EOIs. TDX-SEAM does not allow intercepting EOI. Note, technically KVM could partially emulate the I/O APIC by allowing only edge triggered interrupts, but that adds a lot of complexity for basically zero benefit. Ideally KVM wouldn't even allow I/O APIC route reservation, but disabling that is a train wreck for Qemu. Signed-off-by: Kai Huang Co-developed-by: Sean Christopherson Signed-off-by: Sean Christopherson Signed-off-by: Isaku Yamahata --- arch/x86/include/asm/kvm_host.h | 1 + arch/x86/kvm/ioapic.c | 4 ++++ arch/x86/kvm/irq_comm.c | 9 +++++++-- arch/x86/kvm/lapic.c | 3 ++- arch/x86/kvm/x86.c | 6 ++++++ 5 files changed, 20 insertions(+), 3 deletions(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 5d6143643cd1..f373d672b4ac 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -1054,6 +1054,7 @@ struct kvm_arch { enum kvm_irqchip_mode irqchip_mode; u8 nr_reserved_ioapic_pins; + bool eoi_intercept_unsupported; bool disabled_lapic_found; diff --git a/arch/x86/kvm/ioapic.c b/arch/x86/kvm/ioapic.c index 698969e18fe3..e2de6e552d25 100644 --- a/arch/x86/kvm/ioapic.c +++ b/arch/x86/kvm/ioapic.c @@ -311,6 +311,10 @@ void kvm_arch_post_irq_ack_notifier_list_update(struct kvm *kvm) { if (!ioapic_in_kernel(kvm)) return; + + if (WARN_ON_ONCE(kvm->arch.eoi_intercept_unsupported)) + return; + kvm_make_scan_ioapic_request(kvm); } diff --git a/arch/x86/kvm/irq_comm.c b/arch/x86/kvm/irq_comm.c index d5b72a08e566..bcfac99db579 100644 --- a/arch/x86/kvm/irq_comm.c +++ b/arch/x86/kvm/irq_comm.c @@ -123,7 +123,12 @@ EXPORT_SYMBOL_GPL(kvm_set_msi_irq); static inline bool kvm_msi_route_invalid(struct kvm *kvm, struct kvm_kernel_irq_routing_entry *e) { - return kvm->arch.x2apic_format && (e->msi.address_hi & 0xff); + struct msi_msg msg = { .address_lo = e->msi.address_lo, + .address_hi = e->msi.address_hi, + .data = e->msi.data }; + return (kvm->arch.eoi_intercept_unsupported && + msg.arch_data.is_level) || + (kvm->arch.x2apic_format && (msg.address_hi & 0xff)); } int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e, @@ -385,7 +390,7 @@ int kvm_setup_empty_irq_routing(struct kvm *kvm) void kvm_arch_post_irq_routing_update(struct kvm *kvm) { - if (!irqchip_split(kvm)) + if (!irqchip_split(kvm) || kvm->arch.eoi_intercept_unsupported) return; kvm_make_scan_ioapic_request(kvm); } diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index 17fa4ab1b834..977a704e3ff1 100644 --- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -278,7 +278,8 @@ void kvm_recalculate_apic_map(struct kvm *kvm) if (old) call_rcu(&old->rcu, kvm_apic_map_free); - kvm_make_scan_ioapic_request(kvm); + if (!kvm->arch.eoi_intercept_unsupported) + kvm_make_scan_ioapic_request(kvm); } static inline void apic_set_spiv(struct kvm_lapic *apic, u32 val) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 87212d7563ae..92204bbc7ea5 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -5744,6 +5744,9 @@ long kvm_arch_vm_ioctl(struct file *filp, goto create_irqchip_unlock; r = -EINVAL; + if (kvm->arch.eoi_intercept_unsupported) + goto create_irqchip_unlock; + if (kvm->created_vcpus) goto create_irqchip_unlock; @@ -5774,6 +5777,9 @@ long kvm_arch_vm_ioctl(struct file *filp, u.pit_config.flags = KVM_PIT_SPEAKER_DUMMY; goto create_pit; case KVM_CREATE_PIT2: + r = -EINVAL; + if (kvm->arch.eoi_intercept_unsupported) + goto out; r = -EFAULT; if (copy_from_user(&u.pit_config, argp, sizeof(struct kvm_pit_config)))