From patchwork Sat Apr 24 00:46:05 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sean Christopherson X-Patchwork-Id: 12222115 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 D2E8FC433B4 for ; Sat, 24 Apr 2021 00:47:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B59B461462 for ; Sat, 24 Apr 2021 00:47:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244147AbhDXArv (ORCPT ); Fri, 23 Apr 2021 20:47:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36738 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244088AbhDXArr (ORCPT ); Fri, 23 Apr 2021 20:47:47 -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 30585C06174A for ; Fri, 23 Apr 2021 17:47:07 -0700 (PDT) Received: by mail-qk1-x749.google.com with SMTP id g184-20020a3784c10000b02902e385de9adaso15314212qkd.3 for ; Fri, 23 Apr 2021 17:47:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=reply-to:date:in-reply-to:message-id:mime-version:references :subject:from:to:cc; bh=WDHyTgGjim6hk3/xd8JtlILQjW4Wl2Ft0fupXNYGdHc=; b=rvQnQvoP00Y7thOgQbkMO45k+pLyOLGgPtLCI27QOGyOOacF6s5jSWo7yThwKATN2j gRoqPUOPIg6AkpXdKzh/EdXAzIXyvJAbL3JyWI6e7MEPDQe5Y6KR/cpJzkbmQOo7Cv2g oqNuv3Vq4fCHXKP1dWMvFDgnu/lWiDStPzq0RDOJbXuuCyLYDo5CAX0P8NQM4GHHYW1C PSqUlcNQ7Ytju04V1UQmEuoFBdp8VIBcbY9o33dP8BY10NLdCjeURq/0yAP+zgFk/BMk OQYvtHz1eU0ypNg/RkrzVRr0Oi3Cht4n0S9STEhnJV+sNJ2/Bh8c9qaK9rP4cD83Lpgm pm/g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:reply-to:date:in-reply-to:message-id :mime-version:references:subject:from:to:cc; bh=WDHyTgGjim6hk3/xd8JtlILQjW4Wl2Ft0fupXNYGdHc=; b=WCY8Y5jOlx3owyErdEFcjV5odqdV4iZYQZuZmYW1Qaff0A4uZMkfEVXQnauyDVYURS PnMF4jyKzifzcmTBt+KfCUuAvIt34Bn385IeXBKgZivTdoRoQSxsrq4Lns8M9qkQbHlF 1/8llX7wZTPXKF/tCrsT3KyvIOQHPVZNF5Q7XXOwB3cvXjgJLJpHT/JuAk+KgwDEFw8y XeA4Q5vB0/aIdmN2vRttzszkOo2kTEzIH5KhllM+q0inGlMw/Joh2P3u/OdRYC7IlLm/ MPgYDmPgFKS28SjZhOQZUWK6ClViQysPtJFs/nWfJ5GGfEjbXQakk+fNbNCuhcMRhlCr lbKA== X-Gm-Message-State: AOAM532cngI9yIa2BhgH+H7BtzsBtsZLn2WSj20whxrMqz41C8Sub0GT Ul1r5xgP/Gk0RMT7+S3Ii7LTut7D3sI= X-Google-Smtp-Source: ABdhPJxba3jkQY8JoBg2/bwM1Z2vQB+NWcrsdv6irr9VK+VHqlDgSN7t9llZT/MKf+h1RoPbe5u8rIhrzM8= X-Received: from seanjc798194.pdx.corp.google.com ([2620:15c:f:10:ad52:3246:e190:f070]) (user=seanjc job=sendgmr) by 2002:a0c:f247:: with SMTP id z7mr7230997qvl.24.1619225226439; Fri, 23 Apr 2021 17:47:06 -0700 (PDT) Reply-To: Sean Christopherson Date: Fri, 23 Apr 2021 17:46:05 -0700 In-Reply-To: <20210424004645.3950558-1-seanjc@google.com> Message-Id: <20210424004645.3950558-4-seanjc@google.com> Mime-Version: 1.0 References: <20210424004645.3950558-1-seanjc@google.com> X-Mailer: git-send-email 2.31.1.498.g6c1eba8ee3d-goog Subject: [PATCH 03/43] KVM: SVM: Require exact CPUID.0x1 match when stuffing EDX at INIT 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 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Do not allow an inexact CPUID "match" when querying the guest's CPUID.0x1 to stuff EDX during INIT. In the common case, where the guest CPU model is an AMD variant, allowing an inexact match is a nop since KVM doesn't emulate Intel's goofy "out-of-range" logic for AMD and Hygon. If the vCPU model happens to be an Intel variant, an inexact match is possible if and only if the max CPUID leaf is precisely '0'. Aside from the fact that there's probably no CPU in existence with a single CPUID leaf, if the max CPUID leaf is '0', that means that CPUID.0.EAX is '0', and thus an inexact match for CPUID.0x1.EAX will also yield '0'. So, with lots of twisty logic, no functional change intended. Signed-off-by: Sean Christopherson Reviewed-by: Reiji Watanabe --- arch/x86/kvm/svm/svm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index 14ff7f0963e9..b9e3229ddc27 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -1299,7 +1299,7 @@ static void svm_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event) } init_vmcb(vcpu); - kvm_cpuid(vcpu, &eax, &dummy, &dummy, &dummy, false); + kvm_cpuid(vcpu, &eax, &dummy, &dummy, &dummy, true); kvm_rdx_write(vcpu, eax); if (kvm_vcpu_apicv_active(vcpu) && !init_event)