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=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS 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 8DFD9C433E6 for ; Wed, 13 Jan 2021 18:30:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 46443233FC for ; Wed, 13 Jan 2021 18:30:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728333AbhAMSaN (ORCPT ); Wed, 13 Jan 2021 13:30:13 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:32894 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728260AbhAMSaN (ORCPT ); Wed, 13 Jan 2021 13:30:13 -0500 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 09D0DC061575; Wed, 13 Jan 2021 10:29:33 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=5HGRAFQITVRUvJXlrDluatF64Db9+nU6uEXhywkvngg=; b=ATqIEHVY+6AGyqtS0NR9HlbQgO ZUlGt3koP3YMDLhaxHbiwMsFrkulbdojHRkxzrz8cw9LvD/iPNmwguJuKR4qjXD7j0RdIe7ztya46 ZU5GH9GhFuTMmnLr9kDqpd5R0X4TwXFapUIsCAuK3+aOL20MNEviSSt3b30TqM5Jn2qzgXPSevasT I7B4tUDAxUIyjo30w0ka9k9BKoxNgbSUsYiMtMWC3nNFVSYgtLpNMZOxGnaJD0zuGBNfVaYd9UOe7 wa1liy0Q1VWI4zZ+JBYizeilP2/lVqTPQftD6sBbs3puwtCF72iHIg2RcIeAtrWsb9xFMomuKYXWL CrID3s1g==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by casper.infradead.org with esmtpsa (Exim 4.94 #2 (Red Hat Linux)) id 1kzks1-006Z9G-Bi; Wed, 13 Jan 2021 18:28:09 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id D1A443060C5; Wed, 13 Jan 2021 19:27:48 +0100 (CET) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id BD660211618D3; Wed, 13 Jan 2021 19:27:48 +0100 (CET) Date: Wed, 13 Jan 2021 19:27:48 +0100 From: Peter Zijlstra To: Like Xu Cc: Paolo Bonzini , eranian@google.com, kvm@vger.kernel.org, Ingo Molnar , Sean Christopherson , Thomas Gleixner , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , Andi Kleen , Kan Liang , wei.w.wang@intel.com, luwei.kang@intel.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH v3 04/17] perf: x86/ds: Handle guest PEBS overflow PMI and inject it to guest Message-ID: References: <20210104131542.495413-1-like.xu@linux.intel.com> <20210104131542.495413-5-like.xu@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Wed, Jan 13, 2021 at 07:22:09PM +0100, Peter Zijlstra wrote: > Again; for the virt illiterate people here (me); why is it expensive to > check guest DS? Remember, you're trying to get someone that thinks virt is the devil's work (me) to review virt patches. You get to spell things out in detail.