From mboxrd@z Thu Jan 1 00:00:00 1970 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757739Ab0AOOWk (ORCPT ); Fri, 15 Jan 2010 09:22:40 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757008Ab0AOOWj (ORCPT ); Fri, 15 Jan 2010 09:22:39 -0500 Received: from mx1.redhat.com ([209.132.183.28]:65517 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756698Ab0AOOWj (ORCPT ); Fri, 15 Jan 2010 09:22:39 -0500 Date: Fri, 15 Jan 2010 09:22:13 -0500 From: "Frank Ch. Eigler" To: Peter Zijlstra Cc: Jim Keniston , Arnaldo Carvalho de Melo , Frederic Weisbecker , LKML , Mark Wielaard , utrace-devel Subject: Re: [RFC] [PATCH 4/7] Uprobes Implementation Message-ID: <20100115142213.GS4822@redhat.com> References: <1263509380.4875.35.camel@localhost.localdomain> <1263546632.4244.352.camel@laptop> <1263548124.4244.358.camel@laptop> <20100115131037.GP4822@redhat.com> <1263561930.4244.417.camel@laptop> <20100115133825.GQ4822@redhat.com> <1263563276.4244.426.camel@laptop> <20100115140042.GR4822@redhat.com> <1263564403.4244.430.camel@laptop> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1263564403.4244.430.camel@laptop> User-Agent: Mutt/1.4.2.2i Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi - > > Well, I'm not in a position to argue line by line about the necessity > > or the cost of utrace low level guts, but this may represent the most > > practical engineering balance between functionality / modularity / > > undesirably intrusive modifications. > > How intrusive and non-modular is installing a DIE_INT3 notifier? I'm not sure about all the reasons pro/con, but it looks like installing such a systemwide hook would force every userspace breakpoint or kprobe event machine wide to pass through the hypothetical uprobes layer, whether or not applicable to a current task. - FChE