Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751268AbWCEC0k (ORCPT ); Sat, 4 Mar 2006 21:26:40 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750786AbWCEC0k (ORCPT ); Sat, 4 Mar 2006 21:26:40 -0500 Received: from mx1.redhat.com ([66.187.233.31]:2223 "EHLO mx1.redhat.com") by vger.kernel.org with ESMTP id S1750715AbWCEC0j (ORCPT ); Sat, 4 Mar 2006 21:26:39 -0500 Date: Sat, 4 Mar 2006 21:26:04 -0500 From: Dave Jones To: Andrew Morton Cc: 76306.1226@compuserve.com, linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org, ak@suse.de, Ashok Raj Subject: Re: 2.6.16rc5 'found' an extra CPU. Message-ID: <20060305022604.GA1289@redhat.com> Mail-Followup-To: Dave Jones , Andrew Morton , 76306.1226@compuserve.com, linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org, ak@suse.de, Ashok Raj References: <200603011957_MC3-1-B99B-8FFE@compuserve.com> <20060302010953.GA19755@redhat.com> <20060304164238.37d2ea49.akpm@osdl.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20060304164238.37d2ea49.akpm@osdl.org> User-Agent: Mutt/1.4.2.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1565 Lines: 39 On Sat, Mar 04, 2006 at 04:42:38PM -0800, Andrew Morton wrote: > Dave Jones wrote: > > > > On Wed, Mar 01, 2006 at 07:55:25PM -0500, Chuck Ebbert wrote: > > > In-Reply-To: <20060301230317.GF1440@redhat.com> > > > > > > On Wed, 1 Mar 2006 18:03:17, Dave Jones wrote: > > > > > > > (17:59:38:davej@nemesis:~)$ cat /sys/devices/system/cpu/cpu0/topology/core_siblings > > > > 00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000001 > > > > (17:59:47:davej@nemesis:~)$ cat /sys/devices/system/cpu/cpu1/topology/core_siblings > > > > 00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000002 > > > > > > > > Neither of these CPUs are HT / dual-core, so shouldn't these be the same ? > > > > > > Those are bitmaps. 1 => only bit 0 is set => CPU 0 is all alone. > > > > > > Did you really build a 256-CPU SMP kernel or is ACPI ignoring CONFIG_NR_CPUS > > > or something? > > > > Yes, it's =256. > > > > Is that the only way in which to trigger the bug? > > If so, I'd be inclined to hold the fix back for 2.6.17. not had chance to test Ashok's change yet (and probably won't until at least Monday), but Andi's one-liner to limit x86-64's NR_CPUs to 255 instead of 256 did the trick, and is a lot less invasive for 2.6.16 Dave - 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/