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=-18.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,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 E2204C433ED for ; Wed, 19 May 2021 18:16:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B9983611BD for ; Wed, 19 May 2021 18:16:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231277AbhESSSP (ORCPT ); Wed, 19 May 2021 14:18:15 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37026 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229437AbhESSSN (ORCPT ); Wed, 19 May 2021 14:18:13 -0400 Received: from mail-pl1-x62d.google.com (mail-pl1-x62d.google.com [IPv6:2607:f8b0:4864:20::62d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BE2ABC06175F for ; Wed, 19 May 2021 11:16:53 -0700 (PDT) Received: by mail-pl1-x62d.google.com with SMTP id v12so7511364plo.10 for ; Wed, 19 May 2021 11:16:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=CLFOMXpBdE9Bfa/vJlsX+au0pL0rCjWGCqtbO53j0sI=; b=ESQcwON7SLUKOrT+MYax0/AVotfmbb0XsyujjM3thAc1uAFm4jqxH6aP4XxEsmxMWl zuSg/rvCmZyHfkq0P2FIwTYF8PllSOMntj/U7PCjRb1tGOV7WVosv/ibZILgjPXG5UqB ASLIID4F0DTslwl85Dhyd5vhZ59htMiZPWck3Q727lnHUka96w+25PncyAnKvwn7/C8T Ujxg0wat5cPzrjNV1tpUkBXF8VO5o9OJqBABp6fl+dyt1EXr8VzZYfVVnK/jQph6unH3 eutzxDSGV4mfzMJ+hD9wK79iQWjXFbXPqkDPzfRwMkwU4N4MeIcnVz2+9CYdNAq8WK4B 2wAA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=CLFOMXpBdE9Bfa/vJlsX+au0pL0rCjWGCqtbO53j0sI=; b=da6YaKcWbYy5jGlUdRjJ4sWGqDloAZ2bbLRAvcO1Mm/ioNx5G4lI6ak6KYXR2zxsGc FaQ58GnFzJsAl79JKMSA8pUpLrJZzU3pPYq3hV/LpYaQoyAACe306cTAWb0NXf5VPVZF /dtytgtZWBICJ/gZtXN8EUApgfMw6EZ4/VAA/mS5zQII0Bc4ETIBNwU43dA4ST8k2HIh gLD/b4hVRAWIFb+Y66mbhcorpoxBqguTx/CUgqa6syQRrDt+7jk8hmhfkjT/WlDbvdZ3 0w+/GqjlfGcwO0a5TS9O4lgXszpjCAL2HN8SwPBT772iFZezXMc9d1qE/kGl6xpInGgP Bdqw== X-Gm-Message-State: AOAM5311H8WnoyCsjquean4GKh6FgpwqFyRien0xjyemh8znW1G87SC3 GOs2DPxT5dF61o3M/XhJL4IA/cuRVYISLwFVb16//g== X-Google-Smtp-Source: ABdhPJy6NwBBDCQq6YpwLGD5OciCit48q01GnkJo6wDYjUBiUy8kpthyQ0i0x3sO1MiZsK3ub10BV25cuLZsjOfmiZE= X-Received: by 2002:a17:90b:1185:: with SMTP id gk5mr262354pjb.168.1621448213191; Wed, 19 May 2021 11:16:53 -0700 (PDT) MIME-Version: 1.0 References: <20210424004645.3950558-1-seanjc@google.com> <20210424004645.3950558-30-seanjc@google.com> In-Reply-To: <20210424004645.3950558-30-seanjc@google.com> From: Reiji Watanabe Date: Wed, 19 May 2021 11:16:37 -0700 Message-ID: Subject: Re: [PATCH 29/43] KVM: SVM: Tweak order of cr0/cr4/efer writes at RESET/INIT To: Sean Christopherson Cc: Paolo Bonzini , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , kvm@vger.kernel.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org > @@ -1204,18 +1204,13 @@ static void init_vmcb(struct kvm_vcpu *vcpu) > init_sys_seg(&save->ldtr, SEG_TYPE_LDT); > init_sys_seg(&save->tr, SEG_TYPE_BUSY_TSS16); > > + svm_set_cr0(vcpu, X86_CR0_NW | X86_CR0_CD | X86_CR0_ET); > svm_set_cr4(vcpu, 0); > svm_set_efer(vcpu, 0); > save->dr6 = 0xffff0ff0; > kvm_set_rflags(vcpu, X86_EFLAGS_FIXED); > vcpu->arch.regs[VCPU_REGS_RIP] = 0x0000fff0; > > - /* > - * svm_set_cr0() sets PG and WP and clears NW and CD on save->cr0. > - * It also updates the guest-visible cr0 value. > - */ > - svm_set_cr0(vcpu, X86_CR0_NW | X86_CR0_CD | X86_CR0_ET); AMD's APM Vol2 (Table 14-1 in Revision 3.37) says CR0 After INIT will be: CD and NW are unchanged Bit 4 (reserved) = 1 All others = 0 (CR0 will be 0x60000010 after RESET) So, it looks the CR0 value that init_vmcb() sets could be different from what is indicated in the APM for INIT. BTW, Intel's SDM (April 2021 version) says CR0 for Power up/Reset/INIT will be 0x60000010 with the following note. ------------------------------------------------- The CD and NW flags are unchanged, bit 4 is set to 1, all other bits are cleared. ------------------------------------------------- The note is attached as '2' to all Power up/Reset/INIT cases looking at the SDM. I would guess it is erroneous that the note is attached to Power up/Reset though. Thanks, Reiji