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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 12FB3C433DF for ; Wed, 8 Jul 2020 14:22:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D7BF2206E9 for ; Wed, 8 Jul 2020 14:22:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729763AbgGHOWi (ORCPT ); Wed, 8 Jul 2020 10:22:38 -0400 Received: from mga11.intel.com ([192.55.52.93]:49688 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729468AbgGHOWi (ORCPT ); Wed, 8 Jul 2020 10:22:38 -0400 IronPort-SDR: dCvA5WlVPBnTHtyexhzpKz9ZppxMClHr3vvCBWiVPVtkpRwDUwaCXiNo9WE/1nyasRqZTU4iCb EKhWoig0jCyw== X-IronPort-AV: E=McAfee;i="6000,8403,9675"; a="145903017" X-IronPort-AV: E=Sophos;i="5.75,327,1589266800"; d="scan'208";a="145903017" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 08 Jul 2020 07:22:37 -0700 IronPort-SDR: ypnSgETFnURfOh2lY/Di1FrVtyy0tX6IzKv3i1woeeu6NNiCW0dbri/bMNjUS49QgLV/4alj1Y Sab66rb+t1oA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.75,327,1589266800"; d="scan'208";a="322949843" Received: from likexu-mobl1.ccr.corp.intel.com (HELO [10.255.31.237]) ([10.255.31.237]) by FMSMGA003.fm.intel.com with ESMTP; 08 Jul 2020 07:22:34 -0700 Reply-To: like.xu@intel.com Subject: Re: [PATCH] kvm: x86: limit the maximum number of vPMU fixed counters to 3 To: Paolo Bonzini , Like Xu , kvm@vger.kernel.org Cc: Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , linux-kernel@vger.kernel.org References: <20200624015928.118614-1-like.xu@linux.intel.com> <8de3f450-7efd-96ab-fdf8-169b3327e5ac@intel.com> <9b50db05-759e-c95c-35b2-99fba50e6997@redhat.com> From: "Xu, Like" Organization: Intel OTC Message-ID: <3e849687-67f9-ac53-10ff-2b76d4881de4@intel.com> Date: Wed, 8 Jul 2020 22:22:33 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <9b50db05-759e-c95c-35b2-99fba50e6997@redhat.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2020/7/8 19:09, Paolo Bonzini wrote: > On 08/07/20 09:51, Xu, Like wrote: >> Kindly ping. >> >> I think we may need this patch, as we limit the maximum vPMU version to 2: >>     eax.split.version_id = min(cap.version, 2); > I don't think this is a problem. Are you planning to add support for > the fourth counter? Yes, we plan to provide this support on the KVM after fully enabling the fourth counter (and an accompanying special counter) on the host perf side. This may require one or two kernel cycles, so I have to prevent it from being exposed to non-linux guest with this fix. Thanks for your support. Thanks, Like Xu > > Paolo >