Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752498Ab3HZTDJ (ORCPT ); Mon, 26 Aug 2013 15:03:09 -0400 Received: from hrndva-omtalb.mail.rr.com ([71.74.56.122]:4987 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752393Ab3HZTDI (ORCPT ); Mon, 26 Aug 2013 15:03:08 -0400 X-Authority-Analysis: v=2.0 cv=DqnUCRD+ c=1 sm=0 a=Sro2XwOs0tJUSHxCKfOySw==:17 a=Drc5e87SC40A:10 a=4YNYSHFQjk8A:10 a=5SG0PmZfjMsA:10 a=kj9zAlcOel0A:10 a=meVymXHHAAAA:8 a=KGjhK52YXX0A:10 a=jyE81Idm5WYA:10 a=20KFwNOVAAAA:8 a=8Q5PjHOKA_jmC8kFctUA:9 a=CjuIK1q_8ugA:10 a=jEp0ucaQiEUA:10 a=Sro2XwOs0tJUSHxCKfOySw==:117 X-Cloudmark-Score: 0 X-Authenticated-User: X-Originating-IP: 67.255.60.225 Date: Mon, 26 Aug 2013 15:03:04 -0400 From: Steven Rostedt To: Dave Jones Cc: paulmck@linux.vnet.ibm.com, Linux Kernel , Ingo Molnar , Peter Zijlstra , Jiri Olsa Subject: Re: suspicious RCU usage (perf) Message-ID: <20130826150304.090a1025@gandalf.local.home> In-Reply-To: <20130826182907.GB25202@redhat.com> References: <20130826145838.GA8377@redhat.com> <20130826162928.GQ3871@linux.vnet.ibm.com> <20130826133041.3d750b1b@gandalf.local.home> <20130826175012.GA25202@redhat.com> <20130826141814.54dcaa89@gandalf.local.home> <20130826182907.GB25202@redhat.com> X-Mailer: Claws Mail 3.9.2 (GTK+ 2.24.20; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1211 Lines: 34 On Mon, 26 Aug 2013 14:29:07 -0400 Dave Jones wrote: > On Mon, Aug 26, 2013 at 02:18:14PM -0400, Steven Rostedt wrote: > > On Mon, 26 Aug 2013 13:50:12 -0400 > > Dave Jones wrote: > > > > > > This was triggered as a regular user fwiw. > > > I had not been running perf, or any other tracing. It was just left > > > fuzzing over the weekend with no interaction at all. > > > > So you are telling me that ftrace was enabled by a regular user? If so, > > that's a huge issue. > > quite. > > > So my question to you. If you were not running perf or any other > > tracing, and this is all just non-root user. How the hell did perf > > function tracing get started on your box???? > > What mechanisms are available that would trigger it being enabled ? > > Is there some path through sys_perf_open_event that might be > missing a capability check perhaps ? > That's a question for Ingo, Peter or Jiri. -- 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/