Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755348AbYJVPwv (ORCPT ); Wed, 22 Oct 2008 11:52:51 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751872AbYJVPwm (ORCPT ); Wed, 22 Oct 2008 11:52:42 -0400 Received: from ftp.linux-mips.org ([213.58.128.207]:44744 "EHLO ftp.linux-mips.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751032AbYJVPwl (ORCPT ); Wed, 22 Oct 2008 11:52:41 -0400 Date: Wed, 22 Oct 2008 16:52:40 +0100 (BST) From: "Maciej W. Rozycki" To: Ingo Molnar cc: Cyrill Gorcunov , Glauber Costa , LKML , "H. Peter Anvin" , Thomas Gleixner , Max Kellermann Subject: Re: [PATCH -tip] x86: do_boot_cpu - check if we have ESR register In-Reply-To: <20081022142312.GC26372@elte.hu> Message-ID: References: <20081022140009.GA9639@localhost> <20081022141354.GA26372@elte.hu> <20081022141720.GB9639@localhost> <20081022142312.GC26372@elte.hu> User-Agent: Alpine 1.10 (LFD 962 2008-03-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1499 Lines: 32 On Wed, 22 Oct 2008, Ingo Molnar wrote: > ah, Compaq - how many CPUs does that box support? If it's 8 or more then > perhaps they turned off the real local APIC, fudged some chipset glue to > emulate APIC functionality and thus were able to use 8 or more of these > chips? The built-in lapic would only go up to 4 CPUs. (or maybe even > just up to dual, depending on the model) Hmm, interesting. The integrated APIC should support up to 14 CPUs (assuming one ID is needed for the I/O APIC). One cannot preclude silicon errata affecting the less common hardware configurations though. It would be interesting to see a full bootstrap log with all the APIC debug information enabled. That would probably clarify matters a bit. Note that Compaq would have to come with their own solution about the discrete APIC as the 82489DX went out of production many years ago -- ten at the very least. OTOH, they could have stockpiled them back then. ;) This is one of the few manufacturers I would actually suspect doing so as they always seemed keen on going SMP. Good to know we can support these boxes at all these days. > This reminds us that all the is-integrated-lapic checks still matter > today. Quite surprising indeed. Maciej -- 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/