Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757947AbbGHDNu (ORCPT ); Tue, 7 Jul 2015 23:13:50 -0400 Received: from mail4.hitachi.co.jp ([133.145.228.5]:56636 "EHLO mail4.hitachi.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753991AbbGHDNl (ORCPT ); Tue, 7 Jul 2015 23:13:41 -0400 Message-ID: <559C955C.8090109@hitachi.com> Date: Wed, 08 Jul 2015 12:13:32 +0900 From: Masami Hiramatsu Organization: Hitachi, Ltd., Japan User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:31.0) Gecko/20100101 Thunderbird/31.6.0 MIME-Version: 1.0 To: Vince Weaver , Steven Rostedt CC: linux-kernel@vger.kernel.org, Ananth N Mavinakayanahalli , Anil S Keshavamurthy , "David S. Miller" , Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo Subject: Re: perf, kprobes: fuzzer generates huge number of WARNings References: <559B3899.5040802@hitachi.com> <559BAB68.9000009@hitachi.com> <20150707111009.7e357ad7@gandalf.local.home> 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 Content-Length: 11089 Lines: 200 Hi Vince, On 2015/07/08 3:06, Vince Weaver wrote: > On Tue, 7 Jul 2015, Steven Rostedt wrote: > >> On Tue, 7 Jul 2015 11:06:55 -0400 (EDT) >> Probably. If you recompiled the kernel, you need to find the new >> address points. > > should these messages really be spamming the syslog? > > I updated the kprobe to point to the right location again > (this is > > and the fuzzer just generates infinite of these warnings. Maybe they > should be WARN_ONCE rather than plain WARN? > > [ 5447.623713] ------------[ cut here ]------------ > [ 5447.629160] WARNING: CPU: 1 PID: 4158 at kernel/kprobes.c:939 arm_kprobe+0xe3/0xf0() > [ 5447.637944] Failed to arm kprobe-ftrace at ffffffff81196670 (-19) The corresponding code is ---- ret = ftrace_set_filter_ip(&kprobe_ftrace_ops, (unsigned long)p->addr, 0, 0); WARN(ret < 0, "Failed to arm kprobe-ftrace at %p (%d)\n", p->addr, ret); ---- -19 is -ENODEV, and it may be returned from ftrace_set_hash (ftrace_set_filter_ip -> ftrace_set_addr -> ftrace_set_hash) ---- static int ftrace_set_hash(struct ftrace_ops *ops, unsigned char *buf, int len, unsigned long ip, int remove, int reset, int enable) { struct ftrace_hash **orig_hash; struct ftrace_ops_hash old_hash_ops; struct ftrace_hash *old_hash; struct ftrace_hash *hash; int ret; if (unlikely(ftrace_disabled)) return -ENODEV; ---- the ftrace_disabled (I think it would better be renamed to ftrace_died...) is set only if an unrecoverable error happened. So before this message you'll see some other error messages. Thank you, > [ 5447.723237] CPU: 1 PID: 4158 Comm: perf_fuzzer Tainted: G W 4.2.0-rc1+ #169 > [ 5447.732454] Hardware name: LENOVO 10AM000AUS/SHARKBAY, BIOS FBKT72AUS 01/26/2014 > [ 5447.740897] ffffffff81a2894e ffff8801161b3bf8 ffffffff816a0fd3 0000000000000000 > [ 5447.749426] ffff8801161b3c48 ffff8801161b3c38 ffffffff8106ec8a 000000000000aed0 > [ 5447.757931] ffff88011847b810 0000000000000000 ffff8800cd8b8000 ffffffff81d25640 > [ 5447.766463] Call Trace: > [ 5447.769567] [] dump_stack+0x45/0x57 > [ 5447.775569] [] warn_slowpath_common+0x8a/0xc0 > [ 5447.782504] [] warn_slowpath_fmt+0x46/0x50 > [ 5447.789111] [] ? pcpu_alloc+0x36a/0x630 > [ 5447.795466] [] ? vm_insert_mixed+0x40/0x40 > [ 5447.802098] [] arm_kprobe+0xe3/0xf0 > [ 5447.808095] [] enable_kprobe+0x78/0x80 > [ 5447.814353] [] kprobe_register+0x59/0xe0 > [ 5447.820805] [] perf_trace_init+0x1b5/0x2c0 > [ 5447.827471] [] perf_tp_event_init+0x2a/0x50 > [ 5447.834197] [] perf_try_init_event+0x8b/0xa0 > [ 5447.841012] [] perf_init_event+0x133/0x160 > [ 5447.847658] [] ? perf_bp_event+0x90/0x90 > [ 5447.854101] [] perf_event_alloc+0x42a/0x680 > [ 5447.860840] [] SYSC_perf_event_open+0x3c7/0xd20 > [ 5447.867949] [] SyS_perf_event_open+0x9/0x10 > [ 5447.874702] [] entry_SYSCALL_64_fastpath+0x16/0x7a > [ 5447.882093] ---[ end trace 5d38212a775ec3f3 ]--- > [ 5447.887538] ------------[ cut here ]------------ > [ 5447.892984] WARNING: CPU: 1 PID: 4158 at kernel/kprobes.c:943 arm_kprobe+0xae/0xf0() > [ 5447.901755] Failed to init kprobe-ftrace (-19) > [ 5447.985337] CPU: 1 PID: 4158 Comm: perf_fuzzer Tainted: G W 4.2.0-rc1+ #169 > [ 5447.994611] Hardware name: LENOVO 10AM000AUS/SHARKBAY, BIOS FBKT72AUS 01/26/2014 > [ 5448.003174] ffffffff81a2894e ffff8801161b3bf8 ffffffff816a0fd3 0000000000000000 > [ 5448.011805] ffff8801161b3c48 ffff8801161b3c38 ffffffff8106ec8a ffffffff81125c1a > [ 5448.020424] ffff88011847b810 0000000000000000 ffff8800cd8b8000 ffffffff81d25640 > [ 5448.029074] Call Trace: > [ 5448.032265] [] dump_stack+0x45/0x57 > [ 5448.038342] [] warn_slowpath_common+0x8a/0xc0 > [ 5448.045376] [] ? register_ftrace_function+0x4a/0x70 > [ 5448.052930] [] warn_slowpath_fmt+0x46/0x50 > [ 5448.059617] [] ? mutex_unlock+0xe/0x10 > [ 5448.065951] [] arm_kprobe+0xae/0xf0 > [ 5448.072003] [] enable_kprobe+0x78/0x80 > [ 5448.078341] [] kprobe_register+0x59/0xe0 > [ 5448.084823] [] perf_trace_init+0x1b5/0x2c0 > [ 5448.091484] [] perf_tp_event_init+0x2a/0x50 > [ 5448.098212] [] perf_try_init_event+0x8b/0xa0 > [ 5448.105068] [] perf_init_event+0x133/0x160 > [ 5448.111689] [] ? perf_bp_event+0x90/0x90 > [ 5448.118116] [] perf_event_alloc+0x42a/0x680 > [ 5448.124825] [] SYSC_perf_event_open+0x3c7/0xd20 > [ 5448.131946] [] SyS_perf_event_open+0x9/0x10 > [ 5448.138640] [] entry_SYSCALL_64_fastpath+0x16/0x7a > [ 5448.146065] ---[ end trace 5d38212a775ec3f4 ]--- > [ 5448.228748] ------------[ cut here ]------------ > [ 5448.234201] WARNING: CPU: 2 PID: 4247 at kernel/kprobes.c:955 disarm_kprobe+0xf8/0x100() > [ 5448.243366] Failed to init kprobe-ftrace (-19) > [ 5448.327114] CPU: 2 PID: 4247 Comm: perf_fuzzer Tainted: G W 4.2.0-rc1+ #169 > [ 5448.336416] Hardware name: LENOVO 10AM000AUS/SHARKBAY, BIOS FBKT72AUS 01/26/2014 > [ 5448.344935] ffffffff81a2894e ffff8801187a79e8 ffffffff816a0fd3 0000000000000000 > [ 5448.353549] ffff8801187a7a38 ffff8801187a7a28 ffffffff8106ec8a ffffffff81124f6a > [ 5448.362177] ffff88011847b810 ffff88011847b810 ffff88011847b800 ffff8801160c02a8 > [ 5448.370824] Call Trace: > [ 5448.374033] [] dump_stack+0x45/0x57 > [ 5448.380146] [] warn_slowpath_common+0x8a/0xc0 > [ 5448.387148] [] ? unregister_ftrace_function+0x1a/0x50 > [ 5448.394880] [] warn_slowpath_fmt+0x46/0x50 > [ 5448.401603] [] ? mutex_unlock+0xe/0x10 > [ 5448.407920] [] disarm_kprobe+0xf8/0x100 > [ 5448.414326] [] __disable_kprobe+0x99/0xc0 > [ 5448.420874] [] disable_kprobe+0x27/0x50 > [ 5448.427222] [] disable_trace_kprobe+0xc3/0xf0 > [ 5448.434140] [] kprobe_register+0x2d/0xe0 > [ 5448.440586] [] perf_trace_event_unreg.isra.1+0x33/0x90 > [ 5448.448349] [] perf_trace_destroy+0x3c/0x50 > [ 5448.455058] [] tp_perf_event_destroy+0x9/0x10 > [ 5448.461945] [] _free_event+0xc1/0x250 > [ 5448.468093] [] put_event+0x10a/0x150 > [ 5448.474167] [] ? put_event+0x2b/0x150 > [ 5448.480313] [] ? perf_fasync+0x55/0x70 > [ 5448.486552] [] perf_release+0x10/0x20 > [ 5448.492735] [] __fput+0xdc/0x1e0 > [ 5448.498420] [] ____fput+0xe/0x10 > [ 5448.504110] [] task_work_run+0x9b/0xb0 > [ 5448.510315] [] do_exit+0x3a5/0xa90 > [ 5448.516184] [] ? get_signal+0xe2/0x720 > [ 5448.522407] [] do_group_exit+0x54/0xe0 > [ 5448.528671] [] get_signal+0x280/0x720 > [ 5448.534830] [] do_signal+0x28/0xb50 > [ 5448.540792] [] ? __lock_acquire.isra.31+0x3a6/0xf90 > [ 5448.548277] [] ? sys_getppid+0x5/0x80 > [ 5448.554413] [] do_notify_resume+0x62/0x70 > [ 5448.560950] [] retint_signal+0x44/0x86 > [ 5448.567208] ---[ end trace 5d38212a775ec3f5 ]--- > [ 5448.572624] ------------[ cut here ]------------ > [ 5448.578045] WARNING: CPU: 2 PID: 4247 at kernel/kprobes.c:959 disarm_kprobe+0xca/0x100() > [ 5448.587194] Failed to disarm kprobe-ftrace at ffffffff81196670 (-19) > [ 5448.672321] CPU: 2 PID: 4247 Comm: perf_fuzzer Tainted: G W 4.2.0-rc1+ #169 > [ 5448.681431] Hardware name: LENOVO 10AM000AUS/SHARKBAY, BIOS FBKT72AUS 01/26/2014 > [ 5448.689813] ffffffff81a2894e ffff8801187a79e8 ffffffff816a0fd3 0000000000000000 > [ 5448.698271] ffff8801187a7a38 ffff8801187a7a28 ffffffff8106ec8a ffffffff81124f6a > [ 5448.706783] ffff88011847b810 ffff88011847b810 ffff88011847b800 ffff8801160c02a8 > [ 5448.715255] Call Trace: > [ 5448.718342] [] dump_stack+0x45/0x57 > [ 5448.724346] [] warn_slowpath_common+0x8a/0xc0 > [ 5448.731233] [] ? unregister_ftrace_function+0x1a/0x50 > [ 5448.738872] [] warn_slowpath_fmt+0x46/0x50 > [ 5448.745467] [] ? mutex_unlock+0xe/0x10 > [ 5448.751708] [] ? vm_insert_mixed+0x40/0x40 > [ 5448.758336] [] disarm_kprobe+0xca/0x100 > [ 5448.764683] [] __disable_kprobe+0x99/0xc0 > [ 5448.771186] [] disable_kprobe+0x27/0x50 > [ 5448.777504] [] disable_trace_kprobe+0xc3/0xf0 > [ 5448.784424] [] kprobe_register+0x2d/0xe0 > [ 5448.790863] [] perf_trace_event_unreg.isra.1+0x33/0x90 > [ 5448.798558] [] perf_trace_destroy+0x3c/0x50 > [ 5448.805285] [] tp_perf_event_destroy+0x9/0x10 > [ 5448.812218] [] _free_event+0xc1/0x250 > [ 5448.818384] [] put_event+0x10a/0x150 > [ 5448.824422] [] ? put_event+0x2b/0x150 > [ 5448.830593] [] ? perf_fasync+0x55/0x70 > [ 5448.836862] [] perf_release+0x10/0x20 > [ 5448.843023] [] __fput+0xdc/0x1e0 > [ 5448.848709] [] ____fput+0xe/0x10 > [ 5448.854382] [] task_work_run+0x9b/0xb0 > [ 5448.860620] [] do_exit+0x3a5/0xa90 > [ 5448.866469] [] ? get_signal+0xe2/0x720 > [ 5448.872714] [] do_group_exit+0x54/0xe0 > [ 5448.878990] [] get_signal+0x280/0x720 > [ 5448.885163] [] do_signal+0x28/0xb50 > [ 5448.891117] [] ? __lock_acquire.isra.31+0x3a6/0xf90 > [ 5448.898586] [] ? sys_getppid+0x5/0x80 > [ 5448.904712] [] do_notify_resume+0x62/0x70 > [ 5448.911245] [] retint_signal+0x44/0x86 > [ 5448.917526] ---[ end trace 5d38212a775ec3f6 ]--- > > -- Masami HIRAMATSU Linux Technology Research Center, System Productivity Research Dept. Center for Technology Innovation - Systems Engineering Hitachi, Ltd., Research & Development Group E-mail: masami.hiramatsu.pt@hitachi.com -- 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/