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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 3ED27C43613 for ; Thu, 20 Jun 2019 08:36:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1EA702085A for ; Thu, 20 Jun 2019 08:36:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730842AbfFTIgw (ORCPT ); Thu, 20 Jun 2019 04:36:52 -0400 Received: from mail-wr1-f65.google.com ([209.85.221.65]:46257 "EHLO mail-wr1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726081AbfFTIgw (ORCPT ); Thu, 20 Jun 2019 04:36:52 -0400 Received: by mail-wr1-f65.google.com with SMTP id n4so2036835wrw.13 for ; Thu, 20 Jun 2019 01:36:50 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=78XTCBJ6IQe9uXplpuD9BRY7lz4VHH50PsExpp8KaFU=; b=abtrABWm6fr7WDwGhAMd//8J9WJpXcZOExbuxj4z+krCjqWJJ8dx6Y7ImK28uoAFL4 9qlqv2wdIiEOPzh7w4Ndhr3fv1A0o9xj4hOaE/ERnjh2kuBZeTtG75u1NUVmGUnEDoIG 7HXQkdL1OzNTC5JqgxXqO09RBN5TdAk1wew/RcmihNyqq437syFmOav5Vj0ADc7LN+yW 5WFeoKDP/Fi/xBo8i5JKzG0lGPlW4rjXa3KZ54lXSOfu0TNyuM1iunVzCT2k2JFeV+vU hwZWpelegz0BSlqzkUpPCDwtp/H0nO7+waCcsOz87Ud16L77z1W+3yudDqeLCcPimkB1 wOEQ== X-Gm-Message-State: APjAAAXpmj+MUDRHj4U6/90W/92KoSfqcZPR277K0NDpaLi9pyo++u+k 8Sx1t/ea2aY8Xy3TnenVYH0SF/XXQBk= X-Google-Smtp-Source: APXvYqwPvibP8/SSGIkMVjMpSYvP/Q55IC+qHplvCz6Ywcjqwe3zcNYu0+B2xocYRnlWJAQ8dlQ9yQ== X-Received: by 2002:adf:ce03:: with SMTP id p3mr67060669wrn.94.1561019809656; Thu, 20 Jun 2019 01:36:49 -0700 (PDT) Received: from ?IPv6:2001:b07:6468:f312:7822:aa18:a9d8:39ab? ([2001:b07:6468:f312:7822:aa18:a9d8:39ab]) by smtp.gmail.com with ESMTPSA id v67sm5067971wme.24.2019.06.20.01.36.48 (version=TLS1_3 cipher=AEAD-AES128-GCM-SHA256 bits=128/128); Thu, 20 Jun 2019 01:36:49 -0700 (PDT) Subject: Re: [PATCH] KVM: vmx: Fix the broken usage of vmx_xsaves_supported To: Wanpeng Li Cc: Xiaoyao Li , Tao Xu , Radim Krcmar , Thomas Gleixner , Ingo Molnar , Borislav Petkov , "H. Peter Anvin" , kvm , LKML References: <20190620050301.1149-1-tao3.xu@intel.com> From: Paolo Bonzini Message-ID: <165af492-027d-c640-9dea-c4c2d76fa1aa@redhat.com> Date: Thu, 20 Jun 2019 10:36:49 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 20/06/19 10:27, Wanpeng Li wrote: > Agreed, in addition, guest can enable/disable cpuid bits by grub > parameter Through what path? Guest can disable X86_FEATURE_* but that's purely a Linux feature, the few CPUID bits that can change at runtime already call kvm_x86_ops->cpuid_update(). Paolo > , should we call kvm_x86_ops->cpuid_update() in > kvm_vcpu_reset() path to reflect the new guest cpuid influence to > exec_control? e.g. the first boot guest disable xsaves in grub, kvm > disables xsaves in exec_control; then guest reboot w/ xsaves enabled, > it still get an #UD when executing.