Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754909Ab0AVWOY (ORCPT ); Fri, 22 Jan 2010 17:14:24 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754613Ab0AVWOW (ORCPT ); Fri, 22 Jan 2010 17:14:22 -0500 Received: from mx1.redhat.com ([209.132.183.28]:34158 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753169Ab0AVWOW (ORCPT ); Fri, 22 Jan 2010 17:14:22 -0500 Date: Fri, 22 Jan 2010 17:13:48 -0500 From: "Frank Ch. Eigler" To: Linus Torvalds Cc: Oleg Nesterov , Andrew Morton , Stephen Rothwell , Peter Zijlstra , Peter Zijlstra , Fr??d??ric Weisbecker , LKML , Steven Rostedt , Arnaldo Carvalho de Melo , linux-next@vger.kernel.org, "H. Peter Anvin" , utrace-devel@redhat.com, Thomas Gleixner Subject: Re: linux-next: add utrace tree Message-ID: <20100122221348.GA4263@redhat.com> References: <20100121013822.28781960.sfr@canb.auug.org.au> <20100122111747.3c224dfd.sfr@canb.auug.org.au> <20100121163004.8779bd69.akpm@linux-foundation.org> <20100121163145.7e958c3f.akpm@linux-foundation.org> <20100122005147.GD22003@redhat.com> <20100121170541.7425ff10.akpm@linux-foundation.org> <20100122182827.GA13185@redhat.com> <20100122200129.GG22003@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.4.2.2i Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2000 Lines: 49 Hi - On Fri, Jan 22, 2010 at 01:59:11PM -0800, Linus Torvalds wrote: > [...] > > Finally, I don't know how to address the logic of "if a feature > > requires utrace, that's a bad argument for utrace" and at the same > > time "you need to show a killer app for utrace". What could possibly > > satisfy both of those constraints? Please advise. > > The point is, the feature needs to be a killer feature. And I have yet to > hear _any_ such killer feature, especially from a kernel maintenance > standpoint. > The "better ptrace than ptrace" is irrelevant. Sure, we all know ptrace > isn't a wonderful feature. But it's there, and a debugger is going to have > support for it anyway, so what's the _advantage_ of a "better ptrace > interface"? There is absolutely _zero_ advantage, there's just "yet > another interface". We can't get rid of the old one _anyway_. The point is that the intermediate api will allow (and, as the part you clipped out about utrace-gdbstub said, *already has allowed*) alternative plausible interfaces that coexist just fine. > And the seccomp replacement just sounds horrible. Using some tracing > interface to implement security models sounds like the worst idea ever. So all this is about *naming* utrace? It was never built "for tracing", but for (efficient/multiplexed) *control*. That wasn't even its original name -- one of your lieutenants asked roland to change it to utrace. > And like it or not, over the last almost-decade, _not_ having to > have to work with system tap has been a feature, not a problem, for > the kernel community. I don't have a problem with that. We have apprx. never imposed anything on developers who didn't want to use it. There are plenty who have and will. - FChE -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/