Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751486AbWEOStk (ORCPT ); Mon, 15 May 2006 14:49:40 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751623AbWEOStk (ORCPT ); Mon, 15 May 2006 14:49:40 -0400 Received: from mx2.mail.elte.hu ([157.181.151.9]:26804 "EHLO mx2.mail.elte.hu") by vger.kernel.org with ESMTP id S1751486AbWEOStj (ORCPT ); Mon, 15 May 2006 14:49:39 -0400 Date: Mon, 15 May 2006 20:49:35 +0200 From: Ingo Molnar To: Andi Kleen Cc: Andrew Morton , apw@shadowen.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] x86 NUMA panic compile error Message-ID: <20060515184935.GB19576@elte.hu> References: <20060515005637.00b54560.akpm@osdl.org> <200605152013.53728.ak@suse.de> <20060515113439.457f5809.akpm@osdl.org> <200605152037.54242.ak@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200605152037.54242.ak@suse.de> User-Agent: Mutt/1.4.2.1i X-ELTE-SpamScore: -2.8 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-2.8 required=5.9 tests=ALL_TRUSTED,AWL autolearn=no SpamAssassin version=3.0.3 -2.8 ALL_TRUSTED Did not pass through any untrusted hosts 0.0 AWL AWL: From: address is in the auto white-list X-ELTE-VirusStatus: clean Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1505 Lines: 44 * Andi Kleen wrote: > > So shouldn't such a patch remove that code rather than panicing? > > I would be for remove, but apparently we have one or two users in IBM > that run their x440s (32bit only) with CONFIG_NUMA. No distributions > do so though and I would expect x440s to usually run distributions > because they are quite expensive machines. > > My arguments for remove: > - The code is very hackish - it was written before the proper ACPI > infrastructure is in place - and NUMA on 32bit in general needs a lot > of hacks because of the limited ZONE_NORMAL. works fine here now. The whole NUMA code is still quite hackish in general, (including most of arch/x86_64/*/*.c), so i'd not judge based on that. > - NUMA on 32bit is kind of broken by design. well. 32bit itself is broken by design, if you consider RAM larger than say 1GB. > - It isn't used much. it's an enabler of a feature-set that i couldnt test on these boxes otherwise. Look at it like the highmem= boot option. Or consider it a primitive form of NUMA emulation. > - It breaks often Martin says he's daily testing it in his grid. > - It tends to not work on Opterons and hits the users who try it > there. maybe due to the zone alignment problem? Ingo - 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/