Received: by 10.192.165.148 with SMTP id m20csp3595597imm; Mon, 23 Apr 2018 09:05:03 -0700 (PDT) X-Google-Smtp-Source: AIpwx49Brn9T/QTnBFevDyGW2gC65DVScPvDofgXxl7B0syRoURirf2Ke9LieYAQWd1Pjzv2ieEL X-Received: by 10.99.116.67 with SMTP id e3mr17246124pgn.369.1524499503409; Mon, 23 Apr 2018 09:05:03 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1524499503; cv=none; d=google.com; s=arc-20160816; b=RyL0n94XOrKa2T3gCSok2T05Hy1/53fYOkgZ+bKbRKg5nvG+9RBXunmQdkDgZ44EVD mnsjw+ETZDUvLeXLZ06lI/Oxr2QxCM/vu+JLnOCmfF57xV7CHc/PGhnZz3a3Pe3u1UFa PGTorOwYfcIGWGspTjn8sD+hBR+PiWylsttAN+3ba5T9/B9wQbMP2BmLXHZJM+dVdVde GsL/oSonvlcE0Rtch2FVp7ZWJRijjvtga4IHuB5i0VuUp9cGGsJ43NMgnXZWC4QNzjZ8 0gHTFIUx5Qv7T8XjjD08Ovu9Uc3ziGKO0fqZ9RDUgqSKEiolv0bT1ezfueP3zjlc2+jh 913Q== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:content-transfer-encoding :content-language:in-reply-to:mime-version:user-agent:date :message-id:autocrypt:openpgp:from:references:cc:to:subject :arc-authentication-results; bh=dlZioORuWRfoBYSgDJHvA1TnLwZtD7ggHRYAhmR6ev4=; b=hZ+AfbAfAipmyZA5XshF1w5rv7N97EC6Ix7sgwu9/QjcsyNDdSriQWKzESxyC4CK5+ GS562O0Y8tlA0Vml/pB0+DkAb/PDoyVoWWrVy6lwjV+DfXziIesJV+5UmmZU3BNDTuAO watC5ByZfAv+vlVspc2Hu3aXckbfLzsZHZgulHcfsaZZto2Ho1033XkNz8Yr2B4vapxE nME0uTN0V8M7S1fz4s6yC2HwrZunW7ekfXD0x604bGVtkRIZoIkdiNQdZCLbNivFWpGr UVAoLH6Xm6X5mwVHzU94J6TryBWG2rgOOmH3vzNpIIg7V8/VxtNwxhqvAfxp41zVQGqP RXhQ== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=redhat.com Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id u13si10120562pgq.232.2018.04.23.09.04.48; Mon, 23 Apr 2018 09:05:03 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=redhat.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755878AbeDWQDp (ORCPT + 99 others); Mon, 23 Apr 2018 12:03:45 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:52882 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1755138AbeDWQDn (ORCPT ); Mon, 23 Apr 2018 12:03:43 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id A1B62402335F; Mon, 23 Apr 2018 16:03:42 +0000 (UTC) Received: from [10.36.116.110] (ovpn-116-110.ams2.redhat.com [10.36.116.110]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 5D8A783B9A; Mon, 23 Apr 2018 16:03:41 +0000 (UTC) Subject: Re: [PATCH] KVM: X86: Allow userspace to define the microcode version To: Borislav Petkov Cc: Eduardo Habkost , Wanpeng Li , LKML , kvm , =?UTF-8?B?UmFkaW0gS3LEjW3DocWZ?= References: <20180226121509.GE4377@pd.tnic> <24cd527d-5287-f0be-ffe8-eab341bf1d94@redhat.com> <3866d359-0ef8-6a99-6254-84890be62b93@redhat.com> <20180226122205.GG4377@pd.tnic> <20180417202417.GA29865@localhost.localdomain> <20180418090329.GJ29865@localhost.localdomain> <20180423125849.GD22238@pd.tnic> From: Paolo Bonzini Openpgp: preference=signencrypt Autocrypt: addr=pbonzini@redhat.com; prefer-encrypt=mutual; keydata= xsEhBFRCcBIBDqDGsz4K0zZun3jh+U6Z9wNGLKQ0kSFyjN38gMqU1SfP+TUNQepFHb/Gc0E2 CxXPkIBTvYY+ZPkoTh5xF9oS1jqI8iRLzouzF8yXs3QjQIZ2SfuCxSVwlV65jotcjD2FTN04 hVopm9llFijNZpVIOGUTqzM4U55sdsCcZUluWM6x4HSOdw5F5Utxfp1wOjD/v92Lrax0hjiX DResHSt48q+8FrZzY+AUbkUS+Jm34qjswdrgsC5uxeVcLkBgWLmov2kMaMROT0YmFY6A3m1S P/kXmHDXxhe23gKb3dgwxUTpENDBGcfEzrzilWueOeUWiOcWuFOed/C3SyijBx3Av/lbCsHU Vx6pMycNTdzU1BuAroB+Y3mNEuW56Yd44jlInzG2UOwt9XjjdKkJZ1g0P9dwptwLEgTEd3Fo UdhAQyRXGYO8oROiuh+RZ1lXp6AQ4ZjoyH8WLfTLf5g1EKCTc4C1sy1vQSdzIRu3rBIjAvnC tGZADei1IExLqB3uzXKzZ1BZ+Z8hnt2og9hb7H0y8diYfEk2w3R7wEr+Ehk5NQsT2MPI2QBd wEv1/Aj1DgUHZAHzG1QN9S8wNWQ6K9DqHZTBnI1hUlkp22zCSHK/6FwUCuYp1zcAEQEAAc0f UGFvbG8gQm9uemluaSA8Ym9uemluaUBnbnUub3JnPsLBTQQTAQIAIwUCVEJ7AwIbAwcLCQgH AwIBBhUIAgkKCwQWAgMBAh4BAheAAAoJEH4VEAzNNmmxNcwOniaZVLsuy1lW/ntYCA0Caz0i sHpmecK8aWlvL9wpQCk4GlOX9L1emyYXZPmzIYB0IRqmSzAlZxi+A2qm9XOxs5gJ2xqMEXX5 FMtUH3kpkWWJeLqe7z0EoQdUI4EG988uv/tdZyqjUn2XJE+K01x7r3MkUSFz/HZKZiCvYuze VlS0NTYdUt5jBXualvAwNKfxEkrxeHjxgdFHjYWhjflahY7TNRmuqPM/Lx7wAuyoDjlYNE40 Z+Kun4/KjMbjgpcF4Nf3PJQR8qXI6p3so2qsSn91tY7DFSJO6v2HwFJkC2jU95wxfNmTEUZc znXahYbVOwCDJRuPrE5GKFd/XJU9u5hNtr/uYipHij01WXal2cce1S5mn1/HuM1yo1u8xdHy IupCd57EWI948e8BlhpujUCU2tzOb2iYS0kpmJ9/oLVZrOcSZCcCl2P0AaCAsj59z2kwQS9D du0WxUs8waso0Qq6tDEHo8yLCOJDzSz4oojTtWe4zsulVnWV+wu70AioemAT8S6JOtlu60C5 dHgQUD1Tp+ReXpDKXmjbASJx4otvW0qah3o6JaqO79tbDqIvncu3tewwp6c85uZd48JnIOh3 utBAu684nJakbbvZUGikJfxd887ATQRUQnHuAQgAx4dxXO6/Zun0eVYOnr5GRl76+2UrAAem Vv9Yfn2PbDIbxXqLff7oyVJIkw4WdhQIIvvtu5zH24iYjmdfbg8iWpP7NqxUQRUZJEWbx2CR wkMHtOmzQiQ2tSLjKh/cHeyFH68xjeLcinR7jXMrHQK+UCEw6jqi1oeZzGvfmxarUmS0uRuf fAb589AJW50kkQK9VD/9QC2FJISSUDnRC0PawGSZDXhmvITJMdD4TjYrePYhSY4uuIV02v02 8TVAaYbIhxvDY0hUQE4r8ZbGRLn52bEzaIPgl1p/adKfeOUeMReg/CkyzQpmyB1TSk8lDMxQ zCYHXAzwnGi8WU9iuE1P0wARAQABwsEzBBgBAgAJBQJUQnHuAhsMAAoJEH4VEAzNNmmxp1EO oJy0uZggJm7gZKeJ7iUpeX4eqUtqelUw6gU2daz2hE/jsxsTbC/w5piHmk1H1VWDKEM4bQBT uiJ0bfo55SWsUNN+c9hhIX+Y8LEe22izK3w7mRpvGcg+/ZRG4DEMHLP6JVsv5GMpoYwYOmHn plOzCXHvmdlW0i6SrMsBDl9rw4AtIa6bRwWLim1lQ6EM3PWifPrWSUPrPcw4OLSwFk0CPqC4 HYv/7ZnASVkR5EERFF3+6iaaVi5OgBd81F1TCvCX2BEyIDRZLJNvX3TOd5FEN+lIrl26xecz 876SvcOb5SL5SKg9/rCBufdPSjojkGFWGziHiFaYhbuI2E+NfWLJtd+ZvWAAV+O0d8vFFSvr iy9enJ8kxJwhC0ECbSKFY+W1eTIhMD3aeAKY90drozWEyHhENf4l/V+Ja5vOnW+gCDQkGt2Y 1lJAPPSIqZKvHzGShdh8DduC0U3xYkfbGAUvbxeepjgzp0uEnBXfPTy09JGpgWbg0w91GyfT /ujKaGd4vxG2Ei+MMNDmS1SMx7wu0evvQ5kT9NPzyq8R2GIhVSiAd2jioGuTjX6AZCFv3ToO 53DliFMkVTecLptsXaesuUHgL9dKIfvpm+rNXRn9wAwGjk0X/A== Message-ID: <7eeb63dd-5f7f-df91-47b1-7b15005cf45c@redhat.com> Date: Mon, 23 Apr 2018 18:03:40 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.7.0 MIME-Version: 1.0 In-Reply-To: <20180423125849.GD22238@pd.tnic> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.79 on 10.11.54.5 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.6]); Mon, 23 Apr 2018 16:03:42 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.6]); Mon, 23 Apr 2018 16:03:42 +0000 (UTC) for IP:'10.11.54.5' DOMAIN:'int-mx05.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'pbonzini@redhat.com' RCPT:'' Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 23/04/2018 14:58, Borislav Petkov wrote: >>>> QEMU can't get the host value by rdmsr MSR_IA32_UCODE_REV directly >>>> since rdmsr will #GP when ring !=0, any idea? >>> By looking at kvm_get_msr_feature(), it looks like >>> ioctl(system_fd, KVM_GET_MSRS) would return the host MSR value >>> for us. >> Yes, that's exactly what it was introduced for (together with other MSRs >> including VMX capabilities). > Can't qemu do: > > grep microcode /proc/cpuinfo | awk '{ print $3 }' | head -n 1 > > ? Yes, but you took that a statement bit too narrowly. We didn't include KVM_GET_MSRS because microcode version wasn't otherwise available; rather, there's a general need for KVM userspace to know the values of host MSRs, and microcode is an example. Paolo