Received: by 2002:ac0:a5b6:0:0:0:0:0 with SMTP id m51-v6csp2177054imm; Thu, 7 Jun 2018 06:40:59 -0700 (PDT) X-Google-Smtp-Source: ADUXVKKa4aGN679R1byqPYNoSxzC1CUZ5X9k9T4Pz1/29Ed171pWRuPotGQDczXKlzhh/xYokiyR X-Received: by 2002:a17:902:6ac3:: with SMTP id i3-v6mr2105709plt.378.1528378859054; Thu, 07 Jun 2018 06:40:59 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1528378859; cv=none; d=google.com; s=arc-20160816; b=zUQjTtY5t6Fnzik43+A0vuuIKhQqOZiAt2cDZJ4QsSw8bQmZNKIxHYN8UR4ZcNRa4R RRDq9HBK05WpAr4tslrvp6NNt/1pSY9wiu+8Pc2wF0f8GyPk3OFjmBS8KeGGKFo0NYZt TGqq/c88uTComqeDYgOKxpe6cY2IcxveoPk4PyP55Nv3KnS9i6Nmm9ClujTPRUcx4xR4 YEjtmd13sINfhXQoDM7YbBW2a/DCG2TQ0JJ6il4jNr7LdPwJrmxmD8i087wv5DgyqbMj QeUoaVUx0bs6z16GRbgIizn7hkctzBVxyHjSG7pxHz8hPZg/YGUy2MEnWKYWlp7KhJHd YCJw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:user-agent:in-reply-to :content-disposition:mime-version:references:message-id:subject:cc :to:from:date:arc-authentication-results; bh=RP6kNhI1Xm9F/kIXLMbEPBe91Vy2QVTPw7GqAvubSSI=; b=Hb7ll9Sn3r0gaViz1yAMReKdzQQOUTDSGlV+gZpb9OnmL9gGU7GKIk6vYpWcIYWwYb vLCoaKWRAva3KI/c3iIJp9NL0LAve0c7Q3ovEXIkcci5HIQJvgTE/25zBazz5hc2CvWd wZV9MwtnTgKadNmE0476TNaTYQqalkXGqt07HTzr22xMTR4mAbg+A97TH39bAYwKLduh 6PGmULakUy3Sxz82ugDwdDvbPfnlTF9FMqh108y6oaHTXkpuYpIBaZtlmlkpo6Ta3vV2 CmWWgNlqh9cEtnMLouFvP85ZRJRP96/QU9h/ZCafXHxe7hdcP6NYrwm3yceJHGKoLEOc I5aA== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=intel.com Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id v73-v6si24829974pfi.22.2018.06.07.06.40.44; Thu, 07 Jun 2018 06:40:59 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=intel.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932710AbeFGN0s (ORCPT + 99 others); Thu, 7 Jun 2018 09:26:48 -0400 Received: from mga06.intel.com ([134.134.136.31]:60953 "EHLO mga06.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932503AbeFGN0r (ORCPT ); Thu, 7 Jun 2018 09:26:47 -0400 X-Amp-Result: UNSCANNABLE X-Amp-File-Uploaded: False Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by orsmga104.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 07 Jun 2018 06:26:46 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.49,486,1520924400"; d="scan'208";a="235487019" Received: from um.fi.intel.com (HELO um) ([10.237.72.212]) by fmsmga006.fm.intel.com with ESMTP; 07 Jun 2018 06:26:41 -0700 Received: from ash by um with local (Exim 4.91) (envelope-from ) id 1fQuw2-00045O-RR; Thu, 07 Jun 2018 16:26:38 +0300 Date: Thu, 7 Jun 2018 16:26:38 +0300 From: Alexander Shishkin To: Luwei Kang Cc: kvm@vger.kernel.org, tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com, x86@kernel.org, chao.p.peng@linux.intel.com, thomas.lendacky@amd.com, bp@suse.de, Kan.liang@intel.com, Janakarajan.Natarajan@amd.com, dwmw@amazon.co.uk, linux-kernel@vger.kernel.org, alexander.shishkin@linux.intel.com, peterz@infradead.org, mathieu.poirier@linaro.org, kstewart@linuxfoundation.org, gregkh@linuxfoundation.org, pbonzini@redhat.com, rkrcmar@redhat.com, david@redhat.com, bsd@redhat.com, yu.c.zhang@linux.intel.com, joro@8bytes.org Subject: Re: [PATCH v9 06/12] KVM: x86: Add Intel Processor Trace virtualization mode Message-ID: <20180607132638.snnnt5ecwisfgkmy@um.fi.intel.com> References: <1526964735-16566-1-git-send-email-luwei.kang@intel.com> <1526964735-16566-7-git-send-email-luwei.kang@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1526964735-16566-7-git-send-email-luwei.kang@intel.com> User-Agent: NeoMutt/20180323 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, May 22, 2018 at 12:52:09PM +0800, Luwei Kang wrote: > From: Chao Peng > > Intel PT virtualization can be work in one of 2 possible modes: > a. system-wide: trace both host and guest and output to host buffer; > b. host-guest: trace host/guest simultaneous and output to their > respective buffer. I think we discussed this before. That's not the choice that the user needs to make. The only choice that I see is what happens if the guest wants to use PT while it's already in use by the host. Otherwise, each of them gets to use PT as they would. Regards, -- Alex