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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 103B1C433FE for ; Wed, 5 Jan 2022 01:49:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236980AbiAEBt5 (ORCPT ); Tue, 4 Jan 2022 20:49:57 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40680 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236962AbiAEBt4 (ORCPT ); Tue, 4 Jan 2022 20:49:56 -0500 Received: from mail-pl1-x629.google.com (mail-pl1-x629.google.com [IPv6:2607:f8b0:4864:20::629]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1D18EC061761; Tue, 4 Jan 2022 17:49:56 -0800 (PST) Received: by mail-pl1-x629.google.com with SMTP id p14so28271843plf.3; Tue, 04 Jan 2022 17:49:56 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=message-id:date:mime-version:user-agent:subject:content-language:to :cc:references:from:organization:in-reply-to :content-transfer-encoding; bh=FBngTPEkKGMKclGP0jgxcSSrlzNxGXYaIdpSTFqmKCM=; b=VDLH5aWKyMQjoGskHxiwFVkADFp6eqVezg8OIKixHyk4gGsFxJq2MBl4Gv5Bj6hU9T VxrSCFegiQbvRn5BN6klakMrflTrbHqGZlyNhOVvzQ+Bl8xE2i3NDGm2At0Ev2libubR 3wMQF26EeyJmU0NbIoWXfOhAxTafL2oO0XLA6baGtgHBLTZdjeOCr+ioSOkRIY5zlJKC ATeo4Cunl//t5BgXlQqz0ADhc0g8bjVvEc/dcrEIYaIXwLNzCU8FpxFoqxINGSO0rsla 2tSkszmTh2z9Mk6X+26XsMIJkKn6cZyj60hkqcoJ4B9IatVZy64shESFf07S/c+zJziH qZKA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:date:mime-version:user-agent:subject :content-language:to:cc:references:from:organization:in-reply-to :content-transfer-encoding; bh=FBngTPEkKGMKclGP0jgxcSSrlzNxGXYaIdpSTFqmKCM=; b=GPO2XoUSseITKAHP3SQijhOjE5nKCmN7q1EziSRFymZyw5G7qpsDvNj/IerYCiLdpY G85uS1FB3yBKfIxGtwQTV/77+H36ePBhU5vhJfAjgFGSyAFwTRxu0hGrlNqSePmWFdan kJbcmgM/1dCEc1+p2CrlN5S85fNO/XSVzKm7hAOfQSnnC2f1lcM+cNljEE2yZhL7UBp6 //xYzxFOPnJeVDp0iPOFNyt8cyKlwnCvpbGSKP2xwQ+7DjTDFOLIcSmxrNirXuQj7xWP 9T7nOCkipXy3xwf9/Rkl9DybUPz7Dpv1Ynuu/FWb5u4T2USlvmq6FW3O2uJ/7X4AbhvX NK4g== X-Gm-Message-State: AOAM531UTgf7eIvcchr00WLne7KGlH8+mTiDpm6CJqHs6h+CfnrIoM7x JqqvyhPOopwvnZTA9g21T+E= X-Google-Smtp-Source: ABdhPJwpt3SF+XTj3kPEy836ROsz8IVpdU1BSDzuSQGSYszu19SCL991lLNtj+w4O/f27o4SmKFoEA== X-Received: by 2002:a17:902:bb87:b0:148:a2f7:9d8e with SMTP id m7-20020a170902bb8700b00148a2f79d8emr50996520pls.173.1641347395650; Tue, 04 Jan 2022 17:49:55 -0800 (PST) Received: from [192.168.255.10] ([103.7.29.32]) by smtp.gmail.com with ESMTPSA id 93sm549923pjo.26.2022.01.04.17.49.52 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 04 Jan 2022 17:49:55 -0800 (PST) Message-ID: <4a036416-b2db-18b4-25fa-6d4aaddfcdeb@gmail.com> Date: Wed, 5 Jan 2022 09:49:45 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:91.0) Gecko/20100101 Thunderbird/91.4.1 Subject: Re: [PATCH v11 01/17] perf/x86/intel: Add EPT-Friendly PEBS for Ice Lake Server Content-Language: en-US To: Sean Christopherson Cc: Paolo Bonzini , Jim Mattson , Wanpeng Li , Vitaly Kuznetsov , Joerg Roedel , Peter Zijlstra , Like Xu , kvm@vger.kernel.org, linux-kernel@vger.kernel.org References: <20211210133525.46465-1-likexu@tencent.com> <20211210133525.46465-2-likexu@tencent.com> <69ad949e-4788-0f93-46cb-6af6f79a9f24@gmail.com> From: Like Xu Organization: Tencent In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 5/1/2022 1:25 am, Sean Christopherson wrote: > On Fri, Dec 31, 2021, Like Xu wrote: >> On 31/12/2021 2:13 am, Sean Christopherson wrote: >>> On Fri, Dec 10, 2021, Like Xu wrote: >>>> The new hardware facility supporting guest PEBS is only available on >>>> Intel Ice Lake Server platforms for now. KVM will check this field >>>> through perf_get_x86_pmu_capability() instead of hard coding the cpu >>>> models in the KVM code. If it is supported, the guest PEBS capability >>>> will be exposed to the guest. >>> >>> So what exactly is this new feature? I've speed read the cover letter and a few >>> changelogs and didn't find anything that actually explained when this feature does. >>> >> >> Please check Intel SDM Vol3 18.9.5 for this "EPT-Friendly PEBS" feature. >> >> I assume when an unfamiliar feature appears in the patch SUBJECT, >> the reviewer may search for the exact name in the specification. > > C'mon, seriously? How the blazes am I supposed to know that the feature name > is EPT-Friendly PEBS? Or that it's even in the SDM (it's not in the year-old > version of the SDM I currently have open) versus one of the many ISE docs? You're right. The reviewer's time is valuable. Apologies for my wrong assumption. > > This is not hard. Please spend the 30 seconds it takes to write a small blurb > so that reviewers don't have to spend 5+ minutes wondering WTF this does. > > Add support for EPT-Friendly PEBS, a new CPU feature that enlightens PEBS to > translate guest linear address through EPT, and facilitates handling VM-Exits > that occur when accessing PEBS records. More information can be found in the > release of Intel's SDM, Volume 3, 18.9.5 "EPT-Friendly PEBS". Applied and thanks.