From patchwork Wed Feb 28 06:03:31 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Wanpeng Li X-Patchwork-Id: 10246853 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id AA18F60384 for ; Wed, 28 Feb 2018 06:03:58 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 9935020182 for ; Wed, 28 Feb 2018 06:03:58 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 8D4FA25F31; Wed, 28 Feb 2018 06:03:58 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, FREEMAIL_FROM, RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 0746D20182 for ; Wed, 28 Feb 2018 06:03:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751868AbeB1GDo (ORCPT ); Wed, 28 Feb 2018 01:03:44 -0500 Received: from mail-it0-f67.google.com ([209.85.214.67]:35687 "EHLO mail-it0-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751836AbeB1GDl (ORCPT ); Wed, 28 Feb 2018 01:03:41 -0500 Received: by mail-it0-f67.google.com with SMTP id v194so2112526itb.0; Tue, 27 Feb 2018 22:03:40 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=QqbL1hUbP76Rfo9Y89dE6UeqBPoFyWFG+LapFz+OCVM=; b=ojHnFpnnvxHMZ7a+oxL+ZaJfOyGqrhdO1Y1NUg+xabeHbiFCXNp+2CKO6/y7OkkUrR vdrBMpPH/tBSdYNLFa8ePl+j6U+/pFd2Wm7rLGq69L1IslagqTZ13sIbDiHlFWo0l01U FrMPosUDdUtpI0/9/RstCcsLRYEqjyqC06z4KP8ECTgmu2/Qd99UkSS8XD4WIkLy40A9 Fp5KNbf1rITqTI/wWs2v0ZYVNkJQUmibfCvRVfWx7TIxnU7XdA7IxDb7txRRCFQpjdOf ob+DlcOcMBqjxwI2/uDdRa4ajdC2BjnzmRGHELnHNjEvnX0h6y4W6Y6raJX29bmwsjBk d34g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=QqbL1hUbP76Rfo9Y89dE6UeqBPoFyWFG+LapFz+OCVM=; b=gHHyuJeX+RnCxcum4SBmdhGgKOkxiNFJ3YFVP7bhop7si33e8t9mqXFbsUYvpaT5Pg ydiQtSAaNfMKLSeFhxpLahte9nqa1A49zTrwoO6epxVV2QbQez+JlUn2h0vV2j/P/YdQ uSlzpisMcK5/W4ip4PjI7lx77YIG5/Cz2H9GuLzGGH4EB5/YRhsQf47pZy0wIIZZ5stM IjC9/9WtAYuPFGUMJOFY+GFH5p12dzS0vYfEnR2Sgsie3ZZcivpd5LPbN/5BvyLwR9Yw SvWtIf7KX6r5IG7U/xw5pGEEntj97iIgto+9uGuYbvr1oohLN4BufNVeH7sq2zKVpvR+ hWuA== X-Gm-Message-State: APf1xPAuFP7luMktRvc1ZL2vBetcdeq+RYQ3yrC2KASiP3XOKpyj3vag s9yNYgYuYWvXJbeC3wuD5OBa6Q== X-Google-Smtp-Source: AG47ELviTYckYWy+cwNIwE1ifF9yXzcrAYALoFM+lQ+LYJU4ZO/an0wFocJ1/cdcP5WDiqb72yLa7A== X-Received: by 10.36.165.75 with SMTP id w11mr12127095iti.136.1519797820030; Tue, 27 Feb 2018 22:03:40 -0800 (PST) Received: from localhost.localdomain ([203.205.141.123]) by smtp.googlemail.com with ESMTPSA id h63sm852096ith.32.2018.02.27.22.03.37 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Tue, 27 Feb 2018 22:03:39 -0800 (PST) From: Wanpeng Li X-Google-Original-From: Wanpeng Li To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org Cc: Paolo Bonzini , =?UTF-8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= , Liran Alon , Nadav Amit , Borislav Petkov , Tom Lendacky Subject: [PATCH RESEND v5 2/2] KVM: X86: Allow userspace to define the microcode version Date: Wed, 28 Feb 2018 14:03:31 +0800 Message-Id: <1519797811-4560-2-git-send-email-wanpengli@tencent.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1519797811-4560-1-git-send-email-wanpengli@tencent.com> References: <1519797811-4560-1-git-send-email-wanpengli@tencent.com> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Wanpeng Li Linux (among the others) has checks to make sure that certain features aren't enabled on a certain family/model/stepping if the microcode version isn't greater than or equal to a known good version. By exposing the real microcode version, we're preventing buggy guests that don't check that they are running virtualized (i.e., they should trust the hypervisor) from disabling features that are effectively not buggy. Suggested-by: Filippo Sironi Cc: Paolo Bonzini Cc: Radim Krčmář Cc: Liran Alon Cc: Nadav Amit Cc: Borislav Petkov Cc: Tom Lendacky Signed-off-by: Wanpeng Li Reviewed-by: Paolo Bonzini --- v4 -> v5: * microcode_version be u64 and initialized suitable, remote hte shifts v3 -> v4: * add the shifts back v2 -> v3: * remove the shifts * add the MSR_IA32_UCODE_REV version to the "feature MSRs" v1 -> v2: * add MSR_IA32_UCODE_REV to emulated_msrs arch/x86/include/asm/kvm_host.h | 1 + arch/x86/kvm/svm.c | 4 +--- arch/x86/kvm/vmx.c | 1 + arch/x86/kvm/x86.c | 11 +++++++++-- 4 files changed, 12 insertions(+), 5 deletions(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 938d453..df6720f 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -507,6 +507,7 @@ struct kvm_vcpu_arch { u64 smi_count; bool tpr_access_reporting; u64 ia32_xss; + u64 microcode_version; /* * Paging state of the vcpu diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index f874798..312f33f 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -1907,6 +1907,7 @@ static void svm_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event) u32 dummy; u32 eax = 1; + vcpu->arch.microcode_version = 0x01000065; svm->spec_ctrl = 0; if (!init_event) { @@ -3962,9 +3963,6 @@ static int svm_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info) msr_info->data = svm->spec_ctrl; break; - case MSR_IA32_UCODE_REV: - msr_info->data = 0x01000065; - break; case MSR_F15H_IC_CFG: { int family, model; diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 9968906..2cdbea7 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -5781,6 +5781,7 @@ static void vmx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event) vmx->rmode.vm86_active = 0; vmx->spec_ctrl = 0; + vcpu->arch.microcode_version = 0x100000000ULL; vmx->vcpu.arch.regs[VCPU_REGS_RDX] = get_rdx_init_val(); kvm_set_cr8(vcpu, 0); diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index efc8554..5c93cbc 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -1058,6 +1058,7 @@ static unsigned num_emulated_msrs; static u32 msr_based_features[] = { MSR_IA32_ARCH_CAPABILITIES, MSR_F10H_DECFG, + MSR_IA32_UCODE_REV, }; static unsigned int num_msr_based_features; @@ -1065,6 +1066,9 @@ static unsigned int num_msr_based_features; static int kvm_get_msr_feature(struct kvm_msr_entry *msr) { switch (msr->index) { + case MSR_IA32_UCODE_REV: + rdmsrl(msr->index, msr->data); + break; default: if (kvm_x86_ops->get_msr_feature(msr)) return 1; @@ -2260,7 +2264,6 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info) switch (msr) { case MSR_AMD64_NB_CFG: - case MSR_IA32_UCODE_REV: case MSR_IA32_UCODE_WRITE: case MSR_VM_HSAVE_PA: case MSR_AMD64_PATCH_LOADER: @@ -2268,6 +2271,10 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info) case MSR_AMD64_DC_CFG: break; + case MSR_IA32_UCODE_REV: + if (msr_info->host_initiated) + vcpu->arch.microcode_version = data; + break; case MSR_EFER: return set_efer(vcpu, data); case MSR_K7_HWCR: @@ -2563,7 +2570,7 @@ int kvm_get_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info) msr_info->data = 0; break; case MSR_IA32_UCODE_REV: - msr_info->data = 0x100000000ULL; + msr_info->data = vcpu->arch.microcode_version; break; case MSR_MTRRcap: case 0x200 ... 0x2ff: