From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756177Ab3LDXcX (ORCPT ); Wed, 4 Dec 2013 18:32:23 -0500 Received: from mail4.hitachi.co.jp ([133.145.228.5]:58356 "EHLO mail4.hitachi.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751280Ab3LDXcV (ORCPT ); Wed, 4 Dec 2013 18:32:21 -0500 Message-ID: <529FBB7D.3030100@hitachi.com> Date: Thu, 05 Dec 2013 08:32:13 +0900 From: Masami Hiramatsu Organization: Hitachi, Ltd., Japan User-Agent: Mozilla/5.0 (Windows NT 5.2; rv:13.0) Gecko/20120614 Thunderbird/13.0.1 MIME-Version: 1.0 To: Sandeepa Prabhu Cc: Ingo Molnar , Ananth N Mavinakayanahalli , x86@kernel.org, lkml , "Steven Rostedt (Red Hat)" , systemtap@sourceware.org, "David S. Miller" Subject: Re: Re: [PATCH -tip v4 0/6] kprobes: introduce NOKPROBE_SYMBOL() and fixes crash bugs References: <20131204012841.22118.82992.stgit@kbuild-fedora.novalocal> <529EDC14.5070700@hitachi.com> In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org (2013/12/04 17:46), Sandeepa Prabhu wrote: > On 4 December 2013 13:09, Masami Hiramatsu > wrote: >> (2013/12/04 11:54), Sandeepa Prabhu wrote: >>> On 4 December 2013 06:58, Masami Hiramatsu >>> wrote: >>>> Hi, >>>> Here is the version 4 of NOKPORBE_SYMBOL series. >>>> >>>> In this version, I removed the cleanup patches and >>>> add bugfixes I've found, since those bugs will be >>>> critical. >>>> Rest of the cleanup and visible blacklists will be >>>> proposed later in another series. >>>> >>>> Oh, just one new thing, I added a new RFC patch which >>>> removes the dependency of notify_die() from kprobes >>>> miss-hit/recovery path. Since the notify_die() involves >>>> locking and lockdep code which invokes a lot of heavy >>>> printk functions etc. This helped me to minimize the >>>> blacklist and provides more stability for kprobes. >>>> Actually, most of int3 handlers are already called >>>> from do_int3 directly, I think this change is acceptable >>>> too. >>>> >>>> Here is the updates about NOKPROBE_SYMBOL(). >>>> - Now _ASM_NOKPROBE() macro is introduced for assembly >>>> symbols on x86. >>>> - Rename kprobe_blackpoint to kprobe_blacklist_entry >>>> and simplify it. Also NOKPROBE_SYMBOL() macro just >>>> saves the address of non-probe-able symbols. >>>> >>>> --- >>>> >>>> Masami Hiramatsu (6): >>> >>>> kprobes: Prohibit probing on .entry.text code >>>> kprobes: Introduce NOKPROBE_SYMBOL() macro for blacklist >>> Hi Masami, >>> Is it good idea to split "arch/x86" code from generic kernel changes? >>> Then we just need to take above two patches for verifying it on arm64 >>> or other platforms. >> >> Yeah, it can be. >> However I think you can apply it without any problem on arm64 tree too, >> since it "just adds" an asm macro in arch/x86/include/asm/asm.h. >> It should not have any effect for other arch. Could you try it? :) > Hmm, for the second patch, git am failed with: "error: patch failed: > kernel/sched/core.c:2662", > manually patched to resolve it. aarch64 tree is right now at Linux 3.13-rc2. Ah I see, that must be changed because it is the change related to introducing new blacklist itself. It is not solved by splitting arch/x86 change. Thank you, -- Masami HIRAMATSU IT Management Research Dept. Linux Technology Center Hitachi, Ltd., Yokohama Research Laboratory E-mail: masami.hiramatsu.pt@hitachi.com