From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andi Kleen Subject: Re: [GIT PULL] AlacrityVM guest drivers for 2.6.33 Date: Wed, 23 Dec 2009 20:27:05 +0100 Message-ID: <877hsdcwza.fsf@basil.nowhere.org> References: <4B1D4F29.8020309@gmail.com> <87637zdy9g.fsf@basil.nowhere.org> <4B30E654.40702@codemonkey.ws> <200912221701.56840.bzolnier@gmail.com> <4B30F214.80206@codemonkey.ws> <20091223065129.GA19600@elte.hu> <20091223101340.GC20539@basil.fritz.box> <20091223185150.GA9587@elte.hu> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Anthony Liguori , Bartlomiej Zolnierkiewicz , Gregory Haskins , Avi Kivity , kvm@vger.kernel.org, Andrew Morton , torvalds@linux-foundation.org, "linux-kernel@vger.kernel.org" , netdev@vger.kernel.org, "alacrityvm-devel@lists.sourceforge.net" To: Ingo Molnar Return-path: Received: from one.firstfloor.org ([213.235.205.2]:46240 "EHLO one.firstfloor.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754297AbZLWT1K (ORCPT ); Wed, 23 Dec 2009 14:27:10 -0500 In-Reply-To: <20091223185150.GA9587@elte.hu> (Ingo Molnar's message of "Wed, 23 Dec 2009 19:51:50 +0100") Sender: netdev-owner@vger.kernel.org List-ID: Ingo Molnar writes: > Yes, there's (obviously) compatibility requirements and artifacts and past > mistakes (as with any software interface), but you need to admit it to Yes that's exactly what I meant. > yourself that your "virtualization is sloppy just like hardware" claim is just In my experience hardware is a lot less sloppy than software. Imagine your latest CPU had as many regressions as 2.6.32 @) I wish software and even VMs were as good. > a cheap excuse to not do a proper job of interface engineering. Past mistakes cannot be easily fixed. And undoubtedly even the new shiny interfaces will have bugs and problems. Also the behaviour is often not completely understood. Maybe it can be easier debugged with fully available source, but even then it's hard to fix the old software (or rather even if you can fix it deploy the fixes). In that regard it's a lot like hardware. I agree with you that this makes it important to design good interfaces, but again realistically mistakes will be made and they cannot be all fixed retroactively. -Andi -- ak@linux.intel.com -- Speaking for myself only.