Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755778AbYJaByT (ORCPT ); Thu, 30 Oct 2008 21:54:19 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752687AbYJaByJ (ORCPT ); Thu, 30 Oct 2008 21:54:09 -0400 Received: from hrndva-omtalb.mail.rr.com ([71.74.56.124]:61727 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753495AbYJaByI (ORCPT ); Thu, 30 Oct 2008 21:54:08 -0400 Date: Thu, 30 Oct 2008 21:54:00 -0400 (EDT) From: Steven Rostedt X-X-Sender: rostedt@gandalf.stny.rr.com To: "Luis R. Rodriguez" cc: Tim Gardner , Tomas Winkler , reinette chatre , "linux-wireless@vger.kernel.org" , Linux-Kernel Subject: Re: [MEMO] ftrace suckage++ In-Reply-To: <43e72e890810301445r665a0139g752fb1c97069fe59@mail.gmail.com> Message-ID: References: <43e72e890810301445r665a0139g752fb1c97069fe59@mail.gmail.com> User-Agent: Alpine 1.10 (DEB 962 2008-03-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1674 Lines: 41 On Thu, 30 Oct 2008, Luis R. Rodriguez wrote: > As johannes pointed out to me the culprit to the e1000e corruption was > determined to be ftrace related [1]. Well it seems I hit an oops with > ftrace using iwlagn after a simple load of the module using > wireless-testing. I'm not sure if john's tree yet has ftrace fixes. > Both Fedora 10 and Ubuntu 8.10 had dynamic ftrace enabled so users on > these first kernels and using compat-wireless may run into this so > just putting this out there. I'll can check for this flag in > compat-wireless for now and bitch/exit if its enabled unless someone > has a better idea. > > [1] http://lwn.net/Articles/303390/ > > Oops, using wireless-testing and iwlagn with these options enabled: > > CONFIG_HAVE_FTRACE=y > CONFIG_HAVE_DYNAMIC_FTRACE=y > CONFIG_FTRACE=y > CONFIG_DYNAMIC_FTRACE=y > Yes, ftrace in 2.6.27 is known to be broken. That's why 2.6.27.1 labeled it as such. What is currently in Linus's 2.6.28 git tree is a completely rewritten version of the dynamic ftracer, which addresses all of the issues that caused breakage in the 2.6.27 release. Do not use the 2.6.27 dynamic ftracer, it is known bad. 2.6.28 is fine. If you find issues with what is currently in 2.6.28, please let me know. There is currently some, "make allyesconfig" breakage that ftrace caused on archs other than x86,ppc and sparc, but patches to fix them are in queue to Linus. -- 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/