From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751929AbdHGSpU (ORCPT ); Mon, 7 Aug 2017 14:45:20 -0400 Received: from mout.web.de ([217.72.192.78]:62178 "EHLO mout.web.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751429AbdHGSpT (ORCPT ); Mon, 7 Aug 2017 14:45:19 -0400 Subject: Re: kvm_intel fails to load on Conroe CPUs running Linux 4.12 To: Paolo Bonzini , rkrcmar@redhat.com, tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com, x86@kernel.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org References: <27ee7b1f-0390-fca2-4b9c-cfea715328e9@web.de> <596b1df7-7fec-4acf-f19a-67ed4e1ba150@redhat.com> <6726cf9c-8eb5-8930-fca0-8f5867660847@redhat.com> From: Sebastian Rachuj Message-ID: <2a05dd6c-0094-ea3f-ae68-265809817a78@web.de> Date: Mon, 7 Aug 2017 20:43:54 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.2.1 MIME-Version: 1.0 In-Reply-To: <6726cf9c-8eb5-8930-fca0-8f5867660847@redhat.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Provags-ID: V03:K0:yOv3DekMZVp5U1HmrpCuZIxPYoA4sk/7d340fp9fCMhZOcTgspx GPrO5wgtlONWfwQ0/czPWVSfFS/fral59MOhHsKm93N3Y5pwbb3par5JBt/mYbCVydCoHPt Dx/1amsXtPwPB3fQmsOLz5whpynMQmX8KDBLh1H1RF8bncCygNGLItIYtm7Bzqh8KQDf3jI 6cxvn5InVDjtLsbVXi8vg== X-UI-Out-Filterresults: notjunk:1;V01:K0:WPKPk2Y7jDU=:Nw4InttmmciwMDNoVK4bXr p3rJ+ZsbmSTUppMG1GmA2pznL3tumIzrBwGKfPzr7Jq+KmoWmzw6sNB9tTTNGl4G1peJgYbmJ pvAE7IIEriZr/8xc3KLJ7GZQXfBS++ADvsZpiDCCB5Ag+2ZG99s0WkpfXcQ0ktAPcVp+MzvOb 65SHq3rE8BJvE+O8S6rC+f/OiuRlVYxZaDf5eexQVYtEmqaYaHucQiydqh51ojfDblaUTWjaY 1x9oAe4nTMny7W9zK4RpAdBcxspcF1BFdvfkzdGVF7YcvjLl0GPYJB6yxjwGPRgpz3iYmjtpl 8kDdXtE4SYZyhcRWnqUCLuwvCdAHIqca2vnLsvKkkFB7dtezgBqL5bJGBN+/oHzi8yhtuAgx7 Wp4/FwjK/RIBneYMpbZV5yT27juAW3CXovztl76DD8JW8EEx8XR0y97i3YbHQZo9c/jblrdqa i/Z4axM/ZZT4h9DwW/+EGO2BHEnImM6oP0qCB91Aena05Zm9YO07ls8FaOej5XF2XsFEeClUl ExQubXGlLkNETpU/JNoXingE21XsYj9OIDn6a5nbn70zheue4qjH6Hz3EWJuV5oZyNvnNaDHt 7bAN8bBsFfyamldOtPAhOoZsoLiw96nMYWnpV9pgcd9oD0CdjXvmbNQHZiEiPtRHp9CqMfVpw W3saDRZYgpj2K55/aNnG19Is7N6SO1sJcHAqGCG6YAvxRemuQ9olNMZxpbNp7zkTntF2F6UPZ 68hFQwoe3wxSGilCMCF3NMj1+F+W5KfxHZ+VFABb2hrhI6J8SsLq+tZlwtZzAjbSVYpbJvVo5 OS6RrpCUI8xpRkolEnqoDoAVmnItjXBQXlfUhJxHq+WIHhT/dU= Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 07.08.2017 19:50, Paolo Bonzini wrote: > On 07/08/2017 19:17, Sebastian Rachuj wrote: >>>> >>>> Thank you for looking into the issue. My cpuinfo is as follows: >>> >>> Looks like Intel was already differentiating virtualization features >>> across SKUs. Please run the attached script as root to see what other >>> things are different (apparently) between non-Xeon and Xeon Conroes. >> >> Here you are, I hope it helps: > > Not much to say, unfortunately. It's pretty much the same capabilities > as a Prescott/Cedar Mill processor, except that it has MSR bitmaps. It > also lacks FlexPriority compared to the Conroe I had checked. > > It's not great that even the revert patch doesn't apply cleanly---this > is *not* necessarily a boring area of the hypervisor... > > Given the rarity of your machine I'm currently leaning towards _not_ > reverting the change. I'll check another non-Xeon Core 2 tomorrow that > is from December 2008 (IIRC). If that one also lacks vNMI, or if I get > other reports, I suppose I will have to reconsider that. That's unfortunate to hear. Just for completeness, I want to mention a thread in the Archlinux forum, I created, where two other people (Sadar and losko) also complained about not working KVM [1]. Additionally, Linux 4.12 has not reached yet reached distributions with a greater amount of users. If supporting these chips is too much of a hassle, I will probably have to buy a new CPU to enjoy KVM support with a current linux kernel. Anyway, thanks again for figuring this out! [1]: https://bbs.archlinux.org/viewtopic.php?id=228645