From patchwork Tue Sep 14 23:08:39 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sean Christopherson X-Patchwork-Id: 12495129 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=-26.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT,USER_IN_DEF_DKIM_WL 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 CF6C6C433EF for ; Tue, 14 Sep 2021 23:09:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B20C961165 for ; Tue, 14 Sep 2021 23:09:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236229AbhINXKk (ORCPT ); Tue, 14 Sep 2021 19:10:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47874 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236047AbhINXKd (ORCPT ); Tue, 14 Sep 2021 19:10:33 -0400 Received: from mail-qk1-x749.google.com (mail-qk1-x749.google.com [IPv6:2607:f8b0:4864:20::749]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4FFE2C0613BD for ; Tue, 14 Sep 2021 16:08:49 -0700 (PDT) Received: by mail-qk1-x749.google.com with SMTP id y185-20020a3764c20000b02903d2c78226ceso1478125qkb.6 for ; Tue, 14 Sep 2021 16:08:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=reply-to:date:in-reply-to:message-id:mime-version:references :subject:from:to:cc; bh=V3qpi0lvczNO7KTgWpP693fuTWR6dQFfp5JLcqmi85Y=; b=HUsuOM2QFG1ysMczr03r0k4uGkPR5xD5g2w31QLhwVBWtoIwdtyHxXVqcsFKZCIvIe eVhLPwZ5tohR4H5VdcNcWKQRndgZbcdhynzD8Q01zaZo8WtvQRRDEmFhBLD60uxIb0rR 5Bhmjub99aC8sPdXlMXFZDnmg6k45YK2ymk2vkZQu73fHrNvSiE7S+l2rRs100G0JQNV XDPlmS69F8jT1FCRce1hSbWDrjAkVW9LPTWYG2R+AIJjHb27bcn3bMOszuDZhOA8klX/ 65Auw/w5W9ND+HbxE7dQA0RdeAmxlTJALQvpjGcuoN3sixKR2jKHBIK/yaqlTjTX0yHk OaGw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:reply-to:date:in-reply-to:message-id :mime-version:references:subject:from:to:cc; bh=V3qpi0lvczNO7KTgWpP693fuTWR6dQFfp5JLcqmi85Y=; b=aAFL3mpCRtqLA3ffvBIzEETLsqOaaZAtzjoLERKBO2A3hXOVJgiBNdvOp6lzaDzqMu uW/KVEbGIGvc594Y6sITfdIwZVyKyCaEHUlLPE4grfkFvSKTHXpD8OoLqD/fFMM8wu0B 5FLdyd7vMSMn3ArtvhhesFb8pgCdcriaSwpM6k3hJgqDo8yMzLzm7DeqAbKl2lagUG2G Z3UyOZI5R3K/EmS0DNqCL7Cmy39e+lDbXNC5O2AP1XrFdAVXXDSDrWJq7XMmokqDBs6J QvUzbvArCYh7GMgkchFF3RudkWVNKP+5UcLknsfmyADeAldUAvkxlFIQfxg5alJjXIJ2 QaNw== X-Gm-Message-State: AOAM530LsWviX+r986ge/EF2LvKRHT9q3xZozl9sb7fdvq4bsTknTMTk MTyD1AGsRlUZdBEJvax/5kjeqSW1xVo= X-Google-Smtp-Source: ABdhPJxH4EAWoOBfpEAWM9+c8IctCJ6uHzy2P7PMurrVUTglZ93ryVeAe8b2W9qA56AUelRdEnaKQqrzX2c= X-Received: from seanjc798194.pdx.corp.google.com ([2620:15c:90:200:d59f:9874:e5e5:256b]) (user=seanjc job=sendgmr) by 2002:a0c:f38b:: with SMTP id i11mr8055073qvk.42.1631660928472; Tue, 14 Sep 2021 16:08:48 -0700 (PDT) Reply-To: Sean Christopherson Date: Tue, 14 Sep 2021 16:08:39 -0700 In-Reply-To: <20210914230840.3030620-1-seanjc@google.com> Message-Id: <20210914230840.3030620-3-seanjc@google.com> Mime-Version: 1.0 References: <20210914230840.3030620-1-seanjc@google.com> X-Mailer: git-send-email 2.33.0.309.g3052b89438-goog Subject: [PATCH 2/3] KVM: VMX: Move RESET emulation to vmx_vcpu_reset() From: Sean Christopherson To: Paolo Bonzini Cc: Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Reiji Watanabe Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Move vCPU RESET emulation, including initializating of select VMCS state, to vmx_vcpu_reset(). Drop the open coded "vCPU load" sequence, as ->vcpu_reset() is invoked while the vCPU is properly loaded (which is kind of the point of ->vcpu_reset()...). Hopefully KVM will someday expose a dedicated RESET ioctl(), and in the meantime separating "create" from "RESET" is a nice cleanup. Deferring VMCS initialization is effectively a nop as it's impossible to safely access the VMCS between the current call site and its new home, as both the vCPU and the pCPU are put immediately after init_vmcs(), i.e. the VMCS isn't guaranteed to be loaded. Note, task preemption is not a problem as vmx_sched_in() _can't_ touch the VMCS as ->sched_in() is invoked before the vCPU, and thus VMCS, is reloaded. I.e. the preemption path also can't consume VMCS state. Cc: Reiji Watanabe Signed-off-by: Sean Christopherson --- arch/x86/kvm/vmx/vmx.c | 61 +++++++++++++++++++++--------------------- 1 file changed, 31 insertions(+), 30 deletions(-) diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index dc274b4c9912..629427cf8f4e 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -4327,10 +4327,6 @@ static u32 vmx_secondary_exec_control(struct vcpu_vmx *vmx) #define VMX_XSS_EXIT_BITMAP 0 -/* - * Noting that the initialization of Guest-state Area of VMCS is in - * vmx_vcpu_reset(). - */ static void init_vmcs(struct vcpu_vmx *vmx) { if (nested) @@ -4435,10 +4431,39 @@ static void init_vmcs(struct vcpu_vmx *vmx) vmx_setup_uret_msrs(vmx); } +static void __vmx_vcpu_reset(struct kvm_vcpu *vcpu) +{ + struct vcpu_vmx *vmx = to_vmx(vcpu); + + init_vmcs(vmx); + + if (nested) + memcpy(&vmx->nested.msrs, &vmcs_config.nested, sizeof(vmx->nested.msrs)); + + vcpu_setup_sgx_lepubkeyhash(vcpu); + + vmx->nested.posted_intr_nv = -1; + vmx->nested.current_vmptr = -1ull; + vmx->nested.hv_evmcs_vmptr = EVMPTR_INVALID; + + vcpu->arch.microcode_version = 0x100000000ULL; + vmx->msr_ia32_feature_control_valid_bits = FEAT_CTL_LOCKED; + + /* + * Enforce invariant: pi_desc.nv is always either POSTED_INTR_VECTOR + * or POSTED_INTR_WAKEUP_VECTOR. + */ + vmx->pi_desc.nv = POSTED_INTR_VECTOR; + vmx->pi_desc.sn = 1; +} + static void vmx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event) { struct vcpu_vmx *vmx = to_vmx(vcpu); + if (!init_event) + __vmx_vcpu_reset(vcpu); + vmx->rmode.vm86_active = 0; vmx->spec_ctrl = 0; @@ -6797,7 +6822,7 @@ static int vmx_create_vcpu(struct kvm_vcpu *vcpu) { struct vmx_uret_msr *tsx_ctrl; struct vcpu_vmx *vmx; - int i, cpu, err; + int i, err; BUILD_BUG_ON(offsetof(struct vcpu_vmx, vcpu) != 0); vmx = to_vmx(vcpu); @@ -6856,12 +6881,7 @@ static int vmx_create_vcpu(struct kvm_vcpu *vcpu) } vmx->loaded_vmcs = &vmx->vmcs01; - cpu = get_cpu(); - vmx_vcpu_load(vcpu, cpu); - vcpu->cpu = cpu; - init_vmcs(vmx); - vmx_vcpu_put(vcpu); - put_cpu(); + if (cpu_need_virtualize_apic_accesses(vcpu)) { err = alloc_apic_access_page(vcpu->kvm); if (err) @@ -6874,25 +6894,6 @@ static int vmx_create_vcpu(struct kvm_vcpu *vcpu) goto free_vmcs; } - if (nested) - memcpy(&vmx->nested.msrs, &vmcs_config.nested, sizeof(vmx->nested.msrs)); - - vcpu_setup_sgx_lepubkeyhash(vcpu); - - vmx->nested.posted_intr_nv = -1; - vmx->nested.current_vmptr = -1ull; - vmx->nested.hv_evmcs_vmptr = EVMPTR_INVALID; - - vcpu->arch.microcode_version = 0x100000000ULL; - vmx->msr_ia32_feature_control_valid_bits = FEAT_CTL_LOCKED; - - /* - * Enforce invariant: pi_desc.nv is always either POSTED_INTR_VECTOR - * or POSTED_INTR_WAKEUP_VECTOR. - */ - vmx->pi_desc.nv = POSTED_INTR_VECTOR; - vmx->pi_desc.sn = 1; - return 0; free_vmcs: