Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756767AbYFSJOT (ORCPT ); Thu, 19 Jun 2008 05:14:19 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755738AbYFSJOE (ORCPT ); Thu, 19 Jun 2008 05:14:04 -0400 Received: from mx2.mail.elte.hu ([157.181.151.9]:54042 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752430AbYFSJOB (ORCPT ); Thu, 19 Jun 2008 05:14:01 -0400 Date: Thu, 19 Jun 2008 11:13:37 +0200 From: Ingo Molnar To: Daniel Walker Cc: Byron Bradley , Andrew Morton , linux-kernel@vger.kernel.org, kernel-testers@vger.kernel.org, linux-mm@kvack.org, Hua Zhong Subject: Re: 2.6.26-rc5-mm3 Message-ID: <20080619091337.GA15228@elte.hu> References: <20080611225945.4da7bb7f.akpm@linux-foundation.org> <1213811751.11203.73.camel@localhost.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1213811751.11203.73.camel@localhost.localdomain> User-Agent: Mutt/1.5.18 (2008-05-17) X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.3 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1977 Lines: 53 * Daniel Walker wrote: > > On Fri, 2008-06-13 at 00:32 +0100, Byron Bradley wrote: > > Looks like x86 and ARM both fail to boot if PROFILE_LIKELY, FTRACE and > > DYNAMIC_FTRACE are selected. If any one of those three are disabled it > > boots (or fails in some other way which I'm looking at now). The serial > > console output from both machines when they fail to boot is below, let me > > know if there is any other information I can provide. > > I was able to reproduce a hang on x86 with those options. The patch > below is a potential fix. I think we don't want to trace > do_check_likely(), since the ftrace internals might use likely/unlikely > macro's which will just cause recursion back to do_check_likely().. > > Signed-off-by: Daniel Walker > > --- > lib/likely_prof.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > Index: linux-2.6.25/lib/likely_prof.c > =================================================================== > --- linux-2.6.25.orig/lib/likely_prof.c > +++ linux-2.6.25/lib/likely_prof.c > @@ -22,7 +22,7 @@ > > static struct likeliness *likeliness_head; > > -int do_check_likely(struct likeliness *likeliness, unsigned int ret) > +int notrace do_check_likely(struct likeliness *likeliness, unsigned int ret) the better fix would be to add likely_prof.o to this list of exceptions in lib/Makefile: ifdef CONFIG_FTRACE # Do not profile string.o, since it may be used in early boot or vdso CFLAGS_REMOVE_string.o = -pg # Also do not profile any debug utilities CFLAGS_REMOVE_spinlock_debug.o = -pg CFLAGS_REMOVE_list_debug.o = -pg CFLAGS_REMOVE_debugobjects.o = -pg endif instead of adding notrace to the source. Ingo -- 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/