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 3B606C636D4 for ; Wed, 15 Feb 2023 12:00:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233918AbjBOMAj (ORCPT ); Wed, 15 Feb 2023 07:00:39 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57292 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233919AbjBOMAg (ORCPT ); Wed, 15 Feb 2023 07:00:36 -0500 Received: from mail-pj1-x1033.google.com (mail-pj1-x1033.google.com [IPv6:2607:f8b0:4864:20::1033]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 961FA38023; Wed, 15 Feb 2023 04:00:34 -0800 (PST) Received: by mail-pj1-x1033.google.com with SMTP id w14-20020a17090a5e0e00b00233d3b9650eso1903433pjf.4; Wed, 15 Feb 2023 04:00:34 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=lolFf647qX9YrdZwkuBKlkltYDziYbSSD1kp+TXEm3I=; b=Cf14aFmfEkI+hKh9/yYIP1Oa3rWOFsQKVlfWZuD1DnI17BXqULNjto4c4stYz6ZEsq B00yOqbWlga6ZR5vyb57T9+L9PVNKLRzIgInXrARhfN1RUpwKvU/dLOD89BId+ulcwb+ ZiP/sGWilSFnKeuCE8fAVWCAFkd4pbG2gcsP3GjOWw0kL8bZIDVE07gr7rLwPGhFWMMy hpTew/1xyEUapsXVUUVDSzwueXS90J3WjdfeHBIOySk00lutAnVcicXw5IOR4PLhyxDK 8NWWRfCEA7IZXKAJczyykhqsRNXgtQPhuf2FVzlFRIoq54AITjTdX4ANDkPB3+WEsYtf fKOA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=lolFf647qX9YrdZwkuBKlkltYDziYbSSD1kp+TXEm3I=; b=7FcM1sVP9ceazKnCU0somVIBbuChv5BvL06JHuLiaWIeEmrIO7XYi5+RFxeDYVD50l wijQHHoqwMACmang5GgBnXE7IOMO4AjyUIm9zpaYfgAWZ3huxJhMgARqfOicE9fhcQyW yXTAtAjR6QWMwUDWgMCoHNPjGvHq68+QP54klTU/6YF1raac/w/twh5zVdahY9YldiIm qteo4iVb+245ObEk+tO8YEL9rzSpEaomgw+Jt+ym9b1SxzoSq3N2UbdMT/iPg+eUH9tY yACyhQ7GBiXNY0cO2l/seerf0IWtEraOXqMfJRtjQrzh+V5DjeHPilb1dlWPE5TUxJFO KuIA== X-Gm-Message-State: AO0yUKW+KMgWCFizJXid8nmF+ZYl5EP8MGm7Cd/gpwEncI5dwYYY1JlI Z8i7KR3MDVWnAUNTZOrlgCo= X-Google-Smtp-Source: AK7set9cRg8gne7Ug36x4KfBI1KwQbCbQk4ZTo5dQP+lzL+3Wl9btYddHajWY6kQA+ulLlECvAM8TA== X-Received: by 2002:a17:902:c950:b0:19a:85a8:eb30 with SMTP id i16-20020a170902c95000b0019a85a8eb30mr2630871pla.10.1676462434009; Wed, 15 Feb 2023 04:00:34 -0800 (PST) Received: from [192.168.255.10] ([103.7.29.32]) by smtp.gmail.com with ESMTPSA id d18-20020a170902b71200b001930b189b32sm11947675pls.189.2023.02.15.04.00.32 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 15 Feb 2023 04:00:33 -0800 (PST) Message-ID: <73545081-0d82-fce6-43f0-c50aee9416cb@gmail.com> Date: Wed, 15 Feb 2023 20:00:27 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:102.0) Gecko/20100101 Thunderbird/102.7.2 Subject: Re: [PATCH v2 07/21] KVM: x86/pmu: Zero out LBR capabilities during PMU refresh Content-Language: en-US To: Sean Christopherson Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Paolo Bonzini References: <20230210003148.2646712-1-seanjc@google.com> <20230210003148.2646712-8-seanjc@google.com> From: Like Xu In-Reply-To: <20230210003148.2646712-8-seanjc@google.com> 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 10/2/2023 8:31 am, Sean Christopherson wrote: > Note, this is a very theoretical bug, there is no known use case where a > VMM would deliberately enable the vPMU via KVM_SET_CPUID2, and then later > disable the vPMU. That's why we're getting more and more comfortable with selftests and fuzz testing on KVM interfaces. So is there a test for this ?