From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753520Ab0CUVo7 (ORCPT ); Sun, 21 Mar 2010 17:44:59 -0400 Received: from mx1.redhat.com ([209.132.183.28]:59622 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751337Ab0CUVo5 (ORCPT ); Sun, 21 Mar 2010 17:44:57 -0400 Message-ID: <4BA69344.40504@redhat.com> Date: Sun, 21 Mar 2010 23:44:36 +0200 From: Avi Kivity User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.8) Gecko/20100301 Fedora/3.0.3-1.fc12 Thunderbird/3.0.3 MIME-Version: 1.0 To: Ingo Molnar CC: Antoine Martin , Anthony Liguori , Pekka Enberg , "Zhang, Yanmin" , Peter Zijlstra , Sheng Yang , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, Marcelo Tosatti , oerg Roedel , Jes Sorensen , Gleb Natapov , Zachary Amsden , ziteng.huang@intel.com, Arnaldo Carvalho de Melo , Fr?d?ric Weisbecker Subject: Re: [RFC] Unify KVM kernel-space and user-space code into a single project References: <20100318170223.GB9756@elte.hu> <4BA25E66.2050800@redhat.com> <20100318172805.GB26067@elte.hu> <4BA32E1A.2060703@redhat.com> <20100319085346.GG12576@elte.hu> <4BA3747F.60401@codemonkey.ws> <20100321191742.GD25922@elte.hu> <4BA674F1.6070603@nagafix.co.uk> <20100321195903.GA29490@elte.hu> <4BA67D0B.9030705@redhat.com> <20100321210011.GD30194@elte.hu> In-Reply-To: <20100321210011.GD30194@elte.hu> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 03/21/2010 11:00 PM, Ingo Molnar wrote: > * Avi Kivity wrote: > > >> On 03/21/2010 09:59 PM, Ingo Molnar wrote: >> >>> Frankly, i was surprised (and taken slightly off base) by both Avi and Anthony >>> suggesting such a clearly inferior "add a demon to the guest space" solution. >>> It's a usability and deployment non-starter. >>> >> It's only clearly inferior if you ignore every consideration against it. >> It's definitely not a deployment non-starter, see the tons of daemons that >> come with any Linux system. [...] >> > Avi, please dont put arguments into my mouth that i never made. > Sorry, that was not the intent. I meant that putting things into the kernel have disadvantages that must be considered. > My (clearly expressed) argument was that: > > _a new guest-side demon is a transparent instrumentation non-starter_ > > What is so hard to understand about that simple concept? Instrumentation is > good if it's as transparent as possible. > > Of course lots of other features can be done via a new user-space package ... > I believe you can deploy this daemon via a (default) package, without any hassle to users. -- Do not meddle in the internals of kernels, for they are subtle and quick to panic.