Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752868Ab3FZTwS (ORCPT ); Wed, 26 Jun 2013 15:52:18 -0400 Received: from hrndva-omtalb.mail.rr.com ([71.74.56.122]:9509 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752671Ab3FZTwR (ORCPT ); Wed, 26 Jun 2013 15:52:17 -0400 X-Authority-Analysis: v=2.0 cv=KtrPKBqN c=1 sm=0 a=rXTBtCOcEpjy1lPqhTCpEQ==:17 a=mNMOxpOpBa8A:10 a=XqNnylozy48A:10 a=5SG0PmZfjMsA:10 a=IkcTkHD0fZMA:10 a=meVymXHHAAAA:8 a=KGjhK52YXX0A:10 a=pkicDPhlfI0A:10 a=PPorpS72le2Tx5LNLKMA:9 a=QEXdDO2ut3YA:10 a=rXTBtCOcEpjy1lPqhTCpEQ==:117 X-Cloudmark-Score: 0 X-Authenticated-User: X-Originating-IP: 74.67.115.198 Message-ID: <1372276335.18733.271.camel@gandalf.local.home> Subject: Re: frequent softlockups with 3.10rc6. From: Steven Rostedt To: Dave Jones Cc: Oleg Nesterov , "Paul E. McKenney" , Linux Kernel , Linus Torvalds , "Eric W. Biederman" , Andrey Vagin Date: Wed, 26 Jun 2013 15:52:15 -0400 In-Reply-To: <20130626052352.GB31416@redhat.com> References: <20130622013731.GA22918@redhat.com> <20130622173129.GA29375@redhat.com> <20130622215905.GA28238@redhat.com> <20130623143634.GA2000@redhat.com> <20130623150603.GA32313@redhat.com> <20130623160452.GA11740@redhat.com> <20130624155758.GA5993@redhat.com> <20130624173510.GA1321@redhat.com> <20130625153520.GA7784@redhat.com> <1372177414.18733.211.camel@gandalf.local.home> <20130626052352.GB31416@redhat.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.4.4-3 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1522 Lines: 42 On Wed, 2013-06-26 at 01:23 -0400, Dave Jones wrote: > On Tue, Jun 25, 2013 at 12:23:34PM -0400, Steven Rostedt wrote: > > > Now, what we can try to do as well, is to add a trigger to disable > > tracing, which should (I need to check the code) stop tracing on printk. > > To do so: > > > > # echo printk:traceoff > /sys/kernel/debug/tracing/set_ftrace_filter > > > > This will add a trigger to the printk function that when called, will > > disable tracing. If it is hit before you get your trace, you can just > > re-enable tracing with: > > > > # echo 1 > /sys/kernel/debug/tracing/tracing_on > > > > Hmm, no it needs a fix to make this work. I applied a patch below that > > should do this correctly (and will put this into my 3.11 queue). > > > > If you run the test again with this change and with the above filter, it > > should stop the trace before overwriting the first dump, as it should > > ignore the printk output. > > I think something isn't right with this patch. > After 10 hours, I hit the bug again, but... > > (01:21:28:root@binary:tracing)# cat trace > # tracer: preemptirqsoff > # > (01:21:30:root@binary:tracing)# > Did you apply the patch I added to my last email. It should have prevent that form happening :-/ -- Steve -- 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/