Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932342AbWITTsP (ORCPT ); Wed, 20 Sep 2006 15:48:15 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932344AbWITTsP (ORCPT ); Wed, 20 Sep 2006 15:48:15 -0400 Received: from opersys.com ([64.40.108.71]:33797 "EHLO www.opersys.com") by vger.kernel.org with ESMTP id S932342AbWITTsN (ORCPT ); Wed, 20 Sep 2006 15:48:13 -0400 Message-ID: <45119D49.2040607@opersys.com> Date: Wed, 20 Sep 2006 15:58:01 -0400 From: Karim Yaghmour Reply-To: karim@opersys.com Organization: Opersys inc. User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.8.0.6) Gecko/20060804 Fedora/1.0.4-0.5.1.fc5 SeaMonkey/1.0.4 MIME-Version: 1.0 To: Martin Bligh CC: "Frank Ch. Eigler" , Masami Hiramatsu , prasanna@in.ibm.com, Andrew Morton , Ingo Molnar , Mathieu Desnoyers , Paul Mundt , linux-kernel , Jes Sorensen , Tom Zanussi , Richard J Moore , Michel Dagenais , Christoph Hellwig , Greg Kroah-Hartman , Thomas Gleixner , William Cohen , ltt-dev@shafik.org, systemtap@sources.redhat.com, Alan Cox , Michael Davidson Subject: Re: [PATCH] Linux Kernel Markers References: <4510151B.5070304@google.com> <20060919093935.4ddcefc3.akpm@osdl.org> <45101DBA.7000901@google.com> <20060919063821.GB23836@in.ibm.com> <45102641.7000101@google.com> <20060919070516.GD23836@in.ibm.com> <451030A6.6040801@google.com> <45105B5E.9080107@opersys.com> <451141B1.40803@hitachi.com> <451178B0.9030205@opersys.com> <20060920180808.GI18646@redhat.com> <451186F2.3060702@google.com> <45118D63.8070604@opersys.com> <451194DA.40300@google.com> <451199F4.3000006@opersys.com> <45119934.8080001@google.com> In-Reply-To: <45119934.8080001@google.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1079 Lines: 27 Martin Bligh wrote: > You mean using the jump-over thing that was posted earlier? > I thought the CPU erratas prevented doing that atomically > properly. From my understanding of the last 24 hours discussion, > it seemed like the ONLY thing we could do safely atomically was > insert an int3. Which sucks, frankly, but still. No. djprobes already does safely insert other stuff than just int3, that's the whole point. Here are the relevant postings by Hiramatsu-san: http://marc.theaimsgroup.com/?l=linux-kernel&m=115875912510827&w=2 http://marc.theaimsgroup.com/?l=linux-kernel&m=115875867519302&w=2 Unless there's something *I* fundamentally misunderstood from Hiramatsu-san's implementation and input, djprobes can replace the 5-byte filler with a 5-byte unconditional jump. IOW your mechanism works, no int3s involved. Karim - 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/