Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757803AbXEURZa (ORCPT ); Mon, 21 May 2007 13:25:30 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756182AbXEURZX (ORCPT ); Mon, 21 May 2007 13:25:23 -0400 Received: from www.osadl.org ([213.239.205.134]:34579 "EHLO mail.tglx.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1755902AbXEURZW (ORCPT ); Mon, 21 May 2007 13:25:22 -0400 Subject: Re: [stable] [PATCH] Ignore bogus ACPI info for offline CPUs From: Thomas Gleixner To: Chris Wright Cc: Darren Hart , Andrew Morton , Stable Team , Ingo Molnar , LKML , Len Brown In-Reply-To: <20070521170815.GE3429@sequoia.sous-sol.org> References: <1179584570.12981.123.camel@chaos> <200705210947.35350.dvhltc@us.ibm.com> <20070521170815.GE3429@sequoia.sous-sol.org> Content-Type: text/plain Date: Mon, 21 May 2007 19:32:08 +0200 Message-Id: <1179768728.12708.31.camel@chaos> Mime-Version: 1.0 X-Mailer: Evolution 2.8.3 (2.8.3-2.fc6) Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1562 Lines: 40 On Mon, 2007-05-21 at 10:08 -0700, Chris Wright wrote: > * Darren Hart (dvhltc@us.ibm.com) wrote: > > On Saturday 19 May 2007 07:22:50 Thomas Gleixner wrote: > > > Booting a SMP kernel with maxcpus=1 on a SMP system leads to a hard > > > hang, because ACPI ignores the maxcpus setting and sends timer broadcast > > > info for the offline CPUs. This results in a stuck for ever call to > > > smp_call_function_single() on an offline CPU. > > > > > > Ignore the bogus information and print a kernel error to remind ACPI > > > folks to fix it. > > > > > > Affects 2.6.21 / 2.6.22-rc > > > > > > Signed-off-by: Thomas Gleixner > > > > When I first booted with this patch I received the following in a loop: > > > > irq 9: nobody cared (try booting with the "irqpoll" option) > > What happens when booting w/out this patch? Don't want to add known > regression to -stable. See commit log: Booting a SMP kernel with maxcpus=1 on a SMP system leads to a hard hang, because ACPI ignores the maxcpus setting and sends timer broadcast info for the offline CPUs. This results in a stuck for ever call to smp_call_function_single() on an offline CPU. The irq 9 issue is a separate problem and only surfaces on some boxen, but it's not related to this patch. It's related to maxcpus=1 as well. 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/