From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756365Ab0CIBHr (ORCPT ); Mon, 8 Mar 2010 20:07:47 -0500 Received: from cn.fujitsu.com ([222.73.24.84]:49962 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1756324Ab0CIBHo (ORCPT ); Mon, 8 Mar 2010 20:07:44 -0500 Message-ID: <4B959F92.6010701@cn.fujitsu.com> Date: Tue, 09 Mar 2010 09:08:34 +0800 From: Li Zefan User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.1b3pre) Gecko/20090513 Fedora/3.0-2.3.beta2.fc11 Thunderbird/3.0b2 MIME-Version: 1.0 To: rostedt@goodmis.org CC: Frederic Weisbecker , Lai Jiangshan , Ingo Molnar , LKML Subject: Re: [BUG] WARNING: at kernel/trace/ring_buffer.c:3420 References: <4B94936B.8030409@cn.fujitsu.com> <1268060058.10871.1796.camel@gandalf.stny.rr.com> In-Reply-To: <1268060058.10871.1796.camel@gandalf.stny.rr.com> Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Steven Rostedt wrote: > On Mon, 2010-03-08 at 14:04 +0800, Li Zefan wrote: >> While running a ftrace test, a kernel warning showed up. The bug is not so >> easy to reproduce, normally it takes 30 mins to 2 hours. > > What test are you running? Can you share it? > The test runs 10+ processes, reading/writing files in debugfs/tracing/ simultaneously. I'll send it to you in a private mail. >> After revering 3c05d7482777f15e71bb4cb1ba78dee2800dfec6, I ran the test >> for 15 hours, and the bug seems disapeared. > > So basically, you are reading both the trace and trace_pipe (or > trace_pipe_raw) at the same time? > reading trace, yes. reading trace_pipe, no. Actualy we don't see how this commit relates to the bug. I'll run the test again to be sure on this. > -- Steve > >> ------------[ cut here ]------------ >> WARNING: at kernel/trace/ring_buffer.c:3420 ring_buffer_reset_cpu+0x5a/0x9c() >> Hardware name: PRIMERGY >> Modules linked in: ipt_MASQUERADE iptable_nat nf_nat bridge stp llc deflate zlib_deflate ctr camellia cast5 rmd160 crypto_null ccm serpent blowfish twofish_x86_64 twofish_common ecb xcbc cbc sha256_generic sha512_generic des_generic cryptd aes_x86_64 aes_generic ah6 ah4 esp6 esp4 xfrm4_mode_beet xfrm4_tunnel tunnel4 xfrm4_mode_tunnel xfrm4_mode_transport xfrm6_mode_transport xfrm6_mode_beet ipcomp ipcomp6 xfrm_ipcomp xfrm6_tunnel tunnel6 af_key autofs4 sunrpc ipv6 dm_mirror dm_region_hash dm_log dm_multipath uinput i5k_amb hwmon e1000e i5000_edac edac_core iTCO_wdt iTCO_vendor_support shpchp i2c_i801 i2c_core serio_raw pcspkr pata_acpi ata_generic mptsas mptscsih ata_piix mptbase scsi_transport_sas dm_mod [last unloaded: speedstep_lib] >> Pid: 2108, comm: ftrace_current_ Tainted: G W 2.6.33-tip+ #2 >> Call Trace: >> [] warn_slowpath_common+0x7c/0x94 >> [] warn_slowpath_null+0x14/0x16 >> [] ring_buffer_reset_cpu+0x5a/0x9c >> [] tracing_reset_online_cpus+0x4a/0x79 >> [] tracer_init+0x15/0x20 >> [] tracing_set_tracer+0x1c2/0x1e7 >> [] ? might_fault+0x5c/0xac >> [] tracing_set_trace_write+0x8c/0xbc >> [] ? trace_buffer_lock_reserve+0x21/0x56 >> [] ? trace_current_buffer_lock_reserve+0x16/0x18 >> [] ? retint_swapgs+0x13/0x1b >> [] vfs_write+0xae/0x10b >> [] sys_write+0x4a/0x6e >> [] tracesys+0xd0/0xd5 >> ---[ end trace f7002f0890d5b023 ]--- > > > >