From mboxrd@z Thu Jan 1 00:00:00 1970 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=-8.5 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 5EED4C31E45 for ; Thu, 13 Jun 2019 17:10:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2A2EA205ED for ; Thu, 13 Jun 2019 17:10:02 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="jH9THcz7" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2393605AbfFMRKB (ORCPT ); Thu, 13 Jun 2019 13:10:01 -0400 Received: from mail-wr1-f66.google.com ([209.85.221.66]:36691 "EHLO mail-wr1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2393266AbfFMRDg (ORCPT ); Thu, 13 Jun 2019 13:03:36 -0400 Received: by mail-wr1-f66.google.com with SMTP id n4so21629094wrs.3; Thu, 13 Jun 2019 10:03:34 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:from:to:cc:subject:date:message-id:in-reply-to:references; bh=LNkyAGPk1iKZCEgQnBFbCeLjAmjPtNmmbmMQ3KLc/JY=; b=jH9THcz7JwqDftxHoT6yKTB3EfG2eMSMoQRA2zyxLVjXPtWqSn/aiq/+Fc0a9hUomU J+nIhekKfl0hGlWQ8KAcEqRePevH76QmFPp7y+LHN3LvREtM+TOYFZ4TtGU+D7xkT63F GqkKHs6dPhwfrxws3wPkWu6ga8eIVICmsijlAjzfDqrciF3KEOMA9FuOpWLZej22FxTR p9Dp9hzHk7erhotlnjt631nS82RVyUW/GrD0hJFOoI6OUDhFxKEwI17pyX6j0KGCUL3h Cw1GOa4YHrbLppJdt9/LH99YGgL1WjfV5Tt/pK8mo4YOpyDk2CaGUYeh/Aarjd87d+gk MhwA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:from:to:cc:subject:date:message-id :in-reply-to:references; bh=LNkyAGPk1iKZCEgQnBFbCeLjAmjPtNmmbmMQ3KLc/JY=; b=Sfn/vuuDcy6cRsz8Lyxk1g08JWwybeJFrAt6bhuTAMxCab58S3YVH7JKGMVPAttSPC F99iNWmqEuv4hk/xaW4rwioheehdxu9BosiyV/pJKKmor8NPbHDOjqoPDkLRPeBWLgTn drIq3tgaKROh3Y3VM+DIlPzPvQxkL965BQCb1xO6PRjrFsJkuG+8M9Qb47mYr5Pt5/iy 2LMG5wMdOEIm9OWjgSMQ7h6R7Mf7D/LfiJ4n9Ah5Cz4DDYVPn26tKkUciZFsBDHuIaVS DbxxIQZWc0/7T/fBfLsbaCuZAh8rJ1vbKhl0aiNPBYPENxY84Qdew+iybkFxPhbTaQuN mzsw== X-Gm-Message-State: APjAAAWFy4mVkWvSkkacDF1CZB1TyzfIzbPjO4AGMb6TbmpcE0ZPaCC0 lZwHyhZVsDa3pN1YbRrsYNstd2oT X-Google-Smtp-Source: APXvYqzrmOSIeIRT3Hbew41lagbGcge6uoHXX4UaJu1fzQDFPwkiaFbYCAdm1MlLzN2ABLWaC/bvAg== X-Received: by 2002:a05:6000:4b:: with SMTP id k11mr9221466wrx.82.1560445413938; Thu, 13 Jun 2019 10:03:33 -0700 (PDT) Received: from 640k.localdomain ([93.56.166.5]) by smtp.gmail.com with ESMTPSA id a10sm341856wrx.17.2019.06.13.10.03.33 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 13 Jun 2019 10:03:33 -0700 (PDT) From: Paolo Bonzini To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org Cc: Sean Christopherson , vkuznets@redhat.com Subject: [PATCH 03/43] KVM: VMX: Read cached VM-Exit reason to detect external interrupt Date: Thu, 13 Jun 2019 19:02:49 +0200 Message-Id: <1560445409-17363-4-git-send-email-pbonzini@redhat.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1560445409-17363-1-git-send-email-pbonzini@redhat.com> References: <1560445409-17363-1-git-send-email-pbonzini@redhat.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Sean Christopherson Generic x86 code invokes the kvm_x86_ops external interrupt handler on all VM-Exits regardless of the actual exit type. Use the already-cached EXIT_REASON to determine if the VM-Exit was due to an interrupt, thus avoiding an extra VMREAD (to query VM_EXIT_INTR_INFO) for all other types of VM-Exit. In addition to avoiding the extra VMREAD, checking the EXIT_REASON instead of VM_EXIT_INTR_INFO makes it more obvious that vmx_handle_external_intr() is called for all VM-Exits, e.g. someone unfamiliar with the flow might wonder under what condition(s) VM_EXIT_INTR_INFO does not contain a valid interrupt, which is simply not possible since KVM always runs with "ack interrupt on exit". WARN once if VM_EXIT_INTR_INFO doesn't contain a valid interrupt on an EXTERNAL_INTERRUPT VM-Exit, as such a condition would indicate a hardware bug. Signed-off-by: Sean Christopherson Signed-off-by: Paolo Bonzini --- arch/x86/kvm/vmx/vmcs.h | 6 +++++ arch/x86/kvm/vmx/vmx.c | 62 ++++++++++++++++++++++++++----------------------- 2 files changed, 39 insertions(+), 29 deletions(-) diff --git a/arch/x86/kvm/vmx/vmcs.h b/arch/x86/kvm/vmx/vmcs.h index cb6079f8a227..971a46c69df4 100644 --- a/arch/x86/kvm/vmx/vmcs.h +++ b/arch/x86/kvm/vmx/vmcs.h @@ -115,6 +115,12 @@ static inline bool is_nmi(u32 intr_info) == (INTR_TYPE_NMI_INTR | INTR_INFO_VALID_MASK); } +static inline bool is_external_intr(u32 intr_info) +{ + return (intr_info & (INTR_INFO_VALID_MASK | INTR_INFO_INTR_TYPE_MASK)) + == (INTR_INFO_VALID_MASK | INTR_TYPE_EXT_INTR); +} + enum vmcs_field_width { VMCS_FIELD_WIDTH_U16 = 0, VMCS_FIELD_WIDTH_U64 = 1, diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index da6c829bad9f..b541fe2c6347 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -6127,42 +6127,46 @@ static void vmx_complete_atomic_exit(struct vcpu_vmx *vmx) static void vmx_handle_external_intr(struct kvm_vcpu *vcpu) { - u32 exit_intr_info = vmcs_read32(VM_EXIT_INTR_INFO); - - if ((exit_intr_info & (INTR_INFO_VALID_MASK | INTR_INFO_INTR_TYPE_MASK)) - == (INTR_INFO_VALID_MASK | INTR_TYPE_EXT_INTR)) { - unsigned int vector; - unsigned long entry; - gate_desc *desc; - struct vcpu_vmx *vmx = to_vmx(vcpu); + unsigned int vector; + unsigned long entry; #ifdef CONFIG_X86_64 - unsigned long tmp; + unsigned long tmp; #endif + gate_desc *desc; + u32 intr_info; - vector = exit_intr_info & INTR_INFO_VECTOR_MASK; - desc = (gate_desc *)vmx->host_idt_base + vector; - entry = gate_offset(desc); - asm volatile( + if (to_vmx(vcpu)->exit_reason != EXIT_REASON_EXTERNAL_INTERRUPT) + return; + + intr_info = vmcs_read32(VM_EXIT_INTR_INFO); + if (WARN_ONCE(!is_external_intr(intr_info), + "KVM: unexpected VM-Exit interrupt info: 0x%x", intr_info)) + return; + + vector = intr_info & INTR_INFO_VECTOR_MASK; + desc = (gate_desc *)vmx->host_idt_base + vector; + entry = gate_offset(desc); + + asm volatile( #ifdef CONFIG_X86_64 - "mov %%" _ASM_SP ", %[sp]\n\t" - "and $0xfffffffffffffff0, %%" _ASM_SP "\n\t" - "push $%c[ss]\n\t" - "push %[sp]\n\t" + "mov %%" _ASM_SP ", %[sp]\n\t" + "and $0xfffffffffffffff0, %%" _ASM_SP "\n\t" + "push $%c[ss]\n\t" + "push %[sp]\n\t" #endif - "pushf\n\t" - __ASM_SIZE(push) " $%c[cs]\n\t" - CALL_NOSPEC - : + "pushf\n\t" + __ASM_SIZE(push) " $%c[cs]\n\t" + CALL_NOSPEC + : #ifdef CONFIG_X86_64 - [sp]"=&r"(tmp), + [sp]"=&r"(tmp), #endif - ASM_CALL_CONSTRAINT - : - THUNK_TARGET(entry), - [ss]"i"(__KERNEL_DS), - [cs]"i"(__KERNEL_CS) - ); - } + ASM_CALL_CONSTRAINT + : + THUNK_TARGET(entry), + [ss]"i"(__KERNEL_DS), + [cs]"i"(__KERNEL_CS) + ); } STACK_FRAME_NON_STANDARD(vmx_handle_external_intr); -- 1.8.3.1