Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755005Ab3EIMzi (ORCPT ); Thu, 9 May 2013 08:55:38 -0400 Received: from mail.skyhub.de ([78.46.96.112]:53609 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752556Ab3EIMzh (ORCPT ); Thu, 9 May 2013 08:55:37 -0400 Date: Thu, 9 May 2013 14:58:59 +0200 From: Borislav Petkov To: Jiri Kosina Cc: Frederic Weisbecker , Tony Luck , linux-kernel@vger.kernel.org, x86@kernel.org Subject: Re: NOHZ: WARNING: at arch/x86/kernel/smp.c:123 native_smp_send_reschedule Message-ID: <20130509125859.GG27333@pd.tnic> References: <20130509125040.GF27333@pd.tnic> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20130509125040.GF27333@pd.tnic> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 953 Lines: 24 On Thu, May 09, 2013 at 02:50:40PM +0200, Borislav Petkov wrote: > Looks like we're sending a resched IPI to a cpu which is not online > yet in order to start the MCE polling timer. So the rcu* options are > kinda unlikely to be related, AFAICT. On a second thought, they must be somehow indirectly related because I had "rcu_nocbs=4-7" on the command line and have the warning on the same CPUs: 4 - 7. Actually, NO_HZ_FULL_ALL makes all CPUs full dynticks so I'd guess the RCU callback offloading happens on all of them, thus the warning can happen on every CPU which is in full dynticks mode but not online yet. -- Regards/Gruss, Boris. Sent from a fat crate under my desk. Formatting is fine. -- -- 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/