From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754440Ab3KZH1I (ORCPT ); Tue, 26 Nov 2013 02:27:08 -0500 Received: from mail9.hitachi.co.jp ([133.145.228.44]:49862 "EHLO mail9.hitachi.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753085Ab3KZH1E (ORCPT ); Tue, 26 Nov 2013 02:27:04 -0500 Message-ID: <52944D3E.4000700@hitachi.com> Date: Tue, 26 Nov 2013 16:26:54 +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: Jovi Zhangwei , Steven Rostedt Cc: Oleg Nesterov , LKML , "yrl.pp-manager.tt@hitachi.com" Subject: Re: (ltc-kernel 7837) Re: [BUG] 3.13-rc1 kernel crash when enable all tracepoints References: <5294409F.70508@hitachi.com> In-Reply-To: <5294409F.70508@hitachi.com> 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 (2013/11/26 15:33), Masami Hiramatsu wrote: > (2013/11/26 13:38), Jovi Zhangwei wrote: >> Hi, >> >> I'm not sure this issue already be fixed or not, it can be reproduced >> permanently. >> >> (I didn't use git-bisect yet, you guys might can understand it quickly) >> >> #echo 1 > /sys/kernel/debug/tracing/events/enable > > Thanks for reporting. I could reproduce it. > > To narrow this down, I tried to run the below command > > [tracing]# for i in events/*/*/enable ; do echo $i; echo 1 > $i; done > > And it ran through the end without any problem. > Hm, next I checked the difference of available_events and set_event. > > [tracing]# diff available_events set_event > 283d282 > < ftrace:function > > So, I guess it was caused by enabling ftrace:function, and > it is unable to do that via set_event, nor events/ftrace/enable > I'm not sure how, but it seems that ftrace:function can be > enabled by the events/enable. Oops, No, forget it. When I added a printk in ftrace_set_clr_event_nolock(), it didn't happen and ftrace/function is not enabled. I'm trying to reproduce it on the latest tip kernel again on KVM, but not yet reproduced. Thank you, -- Masami HIRAMATSU IT Management Research Dept. Linux Technology Center Hitachi, Ltd., Yokohama Research Laboratory E-mail: masami.hiramatsu.pt@hitachi.com