From patchwork Thu Dec 13 00:10:26 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jim Mattson X-Patchwork-Id: 10727395 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 3C56E13AF for ; Thu, 13 Dec 2018 00:17:50 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 2D0022B1A4 for ; Thu, 13 Dec 2018 00:17:50 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 213CB2B1A8; Thu, 13 Dec 2018 00:17:50 +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=-15.5 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI, USER_IN_DEF_DKIM_WL autolearn=ham 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 C38A22B1A4 for ; Thu, 13 Dec 2018 00:17:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728537AbeLMARs (ORCPT ); Wed, 12 Dec 2018 19:17:48 -0500 Received: from mail-qt1-f202.google.com ([209.85.160.202]:54587 "EHLO mail-qt1-f202.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726278AbeLMARs (ORCPT ); Wed, 12 Dec 2018 19:17:48 -0500 Received: by mail-qt1-f202.google.com with SMTP id z6so253472qtj.21 for ; Wed, 12 Dec 2018 16:17:47 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:message-id:mime-version:subject:from:to:cc; bh=I7YbaCkuvWQWVxzdePwFfJ7i8vJxzuwCxlMiX/NFYdw=; b=Y/bEC4HPS0sudou5zjLtBX44EdeYH1exGFc9906MAC5N+af1xO9ePHduCEEMbBRe4/ ShlCmHjmCoV3R6+VS9BdyjpbizpHUtf9FK9bT55zNZzKGee6pG2PLEztAKHCc7gdU+7I mvMWPhbyQuYgcwavPP3+w7JNgWLDOZEyE4BdrSqgT1746UQFv0kHOi7GTqo87gRfz9Is RPxwhSthoiS9ghNKzl1BPpp1BGeFxgEhhH3Bv3/yS54h4Luo7WZe5pomZc4R5zBy5iUz MLGtY6QUmEbx//9YFKej87rb0AZzDWGgZocwkEVKqFBeyglEh2euNop68QRZqJw/LJbS Rz3w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:message-id:mime-version:subject:from:to:cc; bh=I7YbaCkuvWQWVxzdePwFfJ7i8vJxzuwCxlMiX/NFYdw=; b=EdgBLFRGOi7EFTqXqJF29RaV92f7wTlwbGHhg/jq/N8krp1S++MQXEkatstZVLkZaj fCIUkciAdPIU2LW+n4sqgyAwe/8pTKI9saSInraU0i8cLYQAc5db6w8gaYpK/nFu0ngT xV+G+Q1V8V/R6KGWEeoi5/DMOcT3NGECo7LVipo8n3X1nIl4jVGpIBOxO5zS9ZDOhzzY Av4r7ZCSk2VcPh+fz3/9V/edjrn0SL+9L2x3JAzKO2d1MsmxSG5Hv8BCVz7bd0/hyE09 5LyDGVZWSkhcyYIzNpkpogq/g/dgM6QStXJkgRjse7JEW3f1MfI0Y1FS+lo1G5oizIhN glfQ== X-Gm-Message-State: AA+aEWbv41h4ujfn/COKP8+YLu2bT1lCJxoQdbiv4O1Bv950uZRdVNgR 9UDG+9YgnSaCkZsBblwergq0+dnyVcGRdM3Bp7/nomcr3SM/XnzmhQDd2M6fgQOHFDhYp92hXH9 IfEsksidxdukFBpNKKn+9S0YeWWL49Pvd0jfvQmvvvHDgUDblNWVou2UGAeAJ1PA= X-Google-Smtp-Source: AFSGD/X8BVJnhX1lmNQUMYxsC8T6iRThe+dyG4HM7k4Gm0hr29XwfgSGiuo7p0CjyK+PdS6bCDI9i1OtyH2JBA== X-Received: by 2002:a0c:9ad6:: with SMTP id k22mr16628232qvf.7.1544659845334; Wed, 12 Dec 2018 16:10:45 -0800 (PST) Date: Wed, 12 Dec 2018 16:10:26 -0800 Message-Id: <20181213001026.178037-1-jmattson@google.com> Mime-Version: 1.0 X-Mailer: git-send-email 2.20.0.rc2.403.gdbc3b29805-goog Subject: [PATCH] kvm: vmx: Pass through IA32_TSC_AUX for read iff guest has RDTSCP From: Jim Mattson To: kvm@vger.kernel.org Cc: Abhiroop Dabral , Jim Mattson , Marc Orr , Peter Shier Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP If the guest supports RDTSCP, it already has read access to the hardware IA32_TSC_AUX MSR via RDTSCP, so we can allow it read-access via RDMSR as well. If the guest doesn't support RDTSCP, then we should not allow it read access to the hardware IA32_TSC_AUX MSR. Signed-off-by: Jim Mattson Reviewed-by: Marc Orr Reviewed-by: Peter Shier Reviewed-by: Krish Sadhukhan Reviewed-by: Sean Christopherson --- arch/x86/kvm/vmx.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index c379d0bfdcba9..69deab6f37953 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -6522,6 +6522,10 @@ static void vmx_compute_secondary_exec_control(struct vcpu_vmx *vmx) if (vmx_rdtscp_supported()) { bool rdtscp_enabled = guest_cpuid_has(vcpu, X86_FEATURE_RDTSCP); + + vmx_set_intercept_for_msr(vmx->vmcs01.msr_bitmap, MSR_TSC_AUX, + MSR_TYPE_R, !rdtscp_enabled); + if (!rdtscp_enabled) exec_control &= ~SECONDARY_EXEC_RDTSCP;