Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755623AbbGCOyN (ORCPT ); Fri, 3 Jul 2015 10:54:13 -0400 Received: from www.linutronix.de ([62.245.132.108]:48533 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754824AbbGCOyG (ORCPT ); Fri, 3 Jul 2015 10:54:06 -0400 Date: Fri, 3 Jul 2015 16:53:49 +0200 (CEST) From: Thomas Gleixner To: Wolfram Sang cc: Simon Horman , Kevin Hilman , Tyler Baker , Borislav Petkov , Geert Uytterhoeven , Magnus Damm , linux-sh@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: Possible regression due to "tick: broadcast: Prevent livelock from event handler" In-Reply-To: <20150703143703.GB19284@katana> Message-ID: References: <20150703024044.GB24695@verge.net.au> <20150703105441.GF1521@katana> <20150703133245.GA19284@katana> <20150703143703.GB19284@katana> User-Agent: Alpine 2.11 (DEB 23 2013-08-11) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1008 Lines: 32 On Fri, 3 Jul 2015, Wolfram Sang wrote: > > So this is a single core machine and uses the em_sti timer w/o the > > broadcast nonsense. In Simons case it looks like em_sti is used as > > broadcast device. > > We use the same board. Just my kernel has SMP=n. > > > Though the issues you see in the highres=n case might be the same as > > the ones Simon is observing. > > I hope so. One good thing about the issue I see is that it is 100% > reproducable. > > > So in that nohz=y highres=n case, does adding idle=poll on the command > > line fix the issue? > > Nope, still hangs. Ok. So it's unrelated to deep idle states. Any chance of poking with JTAG at the frozen box? If not, are there GPIOs which you could use to monitor certain state? Thanks, tglx -- 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/