Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753980AbYFXHPj (ORCPT ); Tue, 24 Jun 2008 03:15:39 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751606AbYFXHPb (ORCPT ); Tue, 24 Jun 2008 03:15:31 -0400 Received: from fgwmail6.fujitsu.co.jp ([192.51.44.36]:48178 "EHLO fgwmail6.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751398AbYFXHPa (ORCPT ); Tue, 24 Jun 2008 03:15:30 -0400 From: "Takashi Nishiie" To: "'Masami Hiramatsu'" , "'Alexey Dobriyan'" Cc: "'Mathieu Desnoyers'" , "'Peter Zijlstra'" , "'Steven Rostedt'" , "'Frank Ch. Eigler'" , "'Ingo Molnar'" , "'LKML'" , "'systemtap-ml'" , "'Hideo AOKI'" References: <485BE2C6.1080901@redhat.com> <20080620174529.GB10943@Krystal> <1213992446.3223.195.camel@lappy.programming.kicks-ass.net> <20080622171135.GA19432@Krystal> <20080622175928.GA5022@martell.zuzino.mipt.ru> <20080622182705.GA23301@Krystal> <20080624002010.GA4777@martell.zuzino.mipt.ru> <486071AF.3080709@redhat.com> In-Reply-To: <486071AF.3080709@redhat.com> Subject: RE: [RFC] Tracepoint proposal Date: Tue, 24 Jun 2008 16:15:35 +0900 Message-ID: <007601c8d5ca$18fa0e10$4aee2a30$@css.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-2022-jp" Content-Transfer-Encoding: 7bit X-Mailer: Microsoft Office Outlook 12.0 Thread-Index: AcjVr3udlatoxZXBQNiaDBqIOeu+xwAGXRGg Content-Language: ja Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1568 Lines: 40 Hi Hiramatsu wrote: >One reason why we need markers or other in-the-middle-of-function >trace point is that some events happen inside functions, not it's >interface. Each kernel sub-system seems to have its own way of dealing with debugging statements. Some of these methods include 'dprintk', 'pr_debug', 'dev_debug', 'DEBUGP'. I think that these functions are the tracepoints that has been availably mounted without setting up the tool set of the outside. I think whether mounting that unites these functions can be done if kernel marker and tracepoint are used. By the way, isn't there problem on security? What kprobe, jprobe, and kernel marker, etc. offer looks like what the framework of Linux Security Module had offered before. Gotten kprobe, jprobe, and kernel marker, etc. should not be exported to the userland for security because it becomes the hotbed of rootkits. Users such as kprobe, jprobe, and kernel marker should not be Loadable Kernel Module. I think that there are some solutions in LTTng about this security problem. However, will the environment to be able to operate SystemTap be really secure? 　At least, kernel commandline option to invalidate all of kprobe, jprobe, and kernel marker, etc. because of the batch might be necessary. Thank you, -- Takashi Nishiie -- 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/