From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 7101 invoked by alias); 28 Nov 2006 15:01:44 -0000 Received: (qmail 7092 invoked by uid 22791); 28 Nov 2006 15:01:43 -0000 X-Spam-Status: No, hits=-2.5 required=5.0 tests=AWL,BAYES_00,SPF_HELO_PASS,SPF_PASS X-Spam-Check-By: sourceware.org Received: from mx1.redhat.com (HELO mx1.redhat.com) (66.187.233.31) by sourceware.org (qpsmtpd/0.31) with ESMTP; Tue, 28 Nov 2006 15:01:34 +0000 Received: from int-mx1.corp.redhat.com (int-mx1.corp.redhat.com [172.16.52.254]) by mx1.redhat.com (8.12.11.20060308/8.12.11) with ESMTP id kASF1W0v006139 for ; Tue, 28 Nov 2006 10:01:32 -0500 Received: from pobox.devel.redhat.com (pobox.devel.redhat.com [10.11.255.8]) by int-mx1.corp.redhat.com (8.13.1/8.13.1) with ESMTP id kASF1VZJ013141; Tue, 28 Nov 2006 10:01:31 -0500 Received: from [10.11.14.216] (vpn-14-216.rdu.redhat.com [10.11.14.216]) by pobox.devel.redhat.com (8.13.1/8.13.1) with ESMTP id kASF1SPO002532; Tue, 28 Nov 2006 10:01:29 -0500 Subject: Re: [RFC][PATCH 0/4][kprobe](djprobe) Direct jump optimized kprobes From: Ingo Molnar To: Masami Hiramatsu Cc: Satoshi Oshima , "Frank Ch. Eigler" , "Keshavamurthy, Anil S" , SystemTAP , Ananth N Mavinakayanahalli , Prasanna S Panchamukhi , Hideo Aoki , Yumiko Sugita , Jim Keniston , Martin Bligh , Greg Kroah-Hartman In-Reply-To: <456C4A5D.8020301@hitachi.com> References: <4562A150.2030606@hitachi.com> <1164632388.22536.109.camel@earth> <456B7D4B.4050202@redhat.com> <1164710436.25787.31.camel@earth> <456C4A5D.8020301@hitachi.com> Content-Type: text/plain Date: Tue, 28 Nov 2006 16:34:00 -0000 Message-Id: <1164726004.25787.56.camel@earth> Mime-Version: 1.0 X-Mailer: Evolution 2.8.1.1 (2.8.1.1-3.fc6) Content-Transfer-Encoding: 7bit Mailing-List: contact systemtap-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Post: List-Help: , Sender: systemtap-owner@sourceware.org X-SW-Source: 2006-q4/txt/msg00545.txt.bz2 On Tue, 2006-11-28 at 23:40 +0900, Masami Hiramatsu wrote: > > If existing in-kernel debug info is not enough then i'd suggest to > add > > an extra build pass to the kernel to add it (dependent on > > CONFIG_KPROBES) - a'la CONFIG_UNWIND_INFO. Am i missing something? > > As far as I know, there is no debuginfo in the kernel which is > loaded in the memory. But the debuginfo is included in the > "vmlinux" file (not the "vmlinuz" file). correct, that sort of debug info is not included in the kernel image - but some of it could be included - just like unwind info, or kallsyms and other info is included currently. Whatever can be extracted at build time we can also insert into the kernel image. The info that is needed here is a table of all valid instruction boundaries, correct? OTOH, userspace (SystemTap) has all this information handy already, because it already has to parse the -g debuginfo - hence it's more natural to delegate this there? Ingo