From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932096Ab3KLQ7n (ORCPT ); Tue, 12 Nov 2013 11:59:43 -0500 Received: from cdptpa-outbound-snat.email.rr.com ([107.14.166.226]:58578 "EHLO cdptpa-oedge-vip.email.rr.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753603Ab3KLQ7l (ORCPT ); Tue, 12 Nov 2013 11:59:41 -0500 Date: Tue, 12 Nov 2013 11:59:35 -0500 From: Steven Rostedt To: Sandeepa Prabhu Cc: Masami Hiramatsu , Will Deacon , "linux-arm-kernel@lists.infradead.org" , "linux-kernel@vger.kernel.org" , "patches@linaro.org" , "linaro-kernel@lists.linaro.org" , Catalin Marinas , "steve.capper@linaro.org" , "nico@linaro.org" , "srikar@linux.vnet.ibm.com" , "dsaxena@linaro.org" , "Vijaya.Kumar@caviumnetworks.com" , Jiang Liu , "yrl.pp-manager.tt@hitachi.com" , Peter Zijlstra , Ingo Molnar Subject: Re: [PATCH RFC 2/6] arm64: Kprobes with single stepping support Message-ID: <20131112115935.23d05236@gandalf.local.home> In-Reply-To: References: <1382008671-4515-1-git-send-email-sandeepa.prabhu@linaro.org> <1382008671-4515-3-git-send-email-sandeepa.prabhu@linaro.org> <20131108165639.GD15074@mudshark.cambridge.arm.com> <527DFC1C.1020107@hitachi.com> <52808D53.7080904@hitachi.com> <5280B6C8.7050807@hitachi.com> <20131111105812.GC28302@mudshark.cambridge.arm.com> <528114C4.5000506@hitachi.com> <5281D848.7000502@hitachi.com> <52820043.6090107@hitachi.com> X-Mailer: Claws Mail 3.9.2 (GTK+ 2.24.20; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-RR-Connecting-IP: 107.14.168.118:25 X-Cloudmark-Score: 0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 12 Nov 2013 16:25:26 +0530 Sandeepa Prabhu wrote: > > > > BTW, I'm currently trying a general housecleaning of __kprobes > > annotations. It may also have impact on your patch. > > https://lkml.org/lkml/2013/11/8/187 > Hmm, we can help testing your patchset on arm64 platforms. Also have > many doubts on the changes you are working [blacklisting probes etc] > > Basically I had tried placing kprobe on memcpy() and the model hung > (insmod never returned back!). Fast-model I have does not have option > of any debug so no clue what happened!. > memcpy() is low-level call being used internally within kprobes, so > probably we cannot handle probe on that routine, but then how to make > sure all such API are rejected by kprobe sub-system ? Working on ports of ftrace, I found that many of the functions in lib/ are used by several locations that just can't be traced, due to how low level they are. I just simply blacklisted the entire lib/ directory (See the top of lib/Makefile) I wonder if there's an easy way to blacklist entire directories from being used by kprobes too. Or at least do it by a file per file basis. -- Steve