Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751102AbWCAD5H (ORCPT ); Tue, 28 Feb 2006 22:57:07 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750943AbWCAD5H (ORCPT ); Tue, 28 Feb 2006 22:57:07 -0500 Received: from zproxy.gmail.com ([64.233.162.201]:2361 "EHLO zproxy.gmail.com") by vger.kernel.org with ESMTP id S1751102AbWCAD5G convert rfc822-to-8bit (ORCPT ); Tue, 28 Feb 2006 22:57:06 -0500 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=beta; d=gmail.com; h=received:message-id:date:from:sender:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=TC55WzJ4aIaSyihSv0rtPvaWO1lXDT5iCbLnphdIe2//5tmRWycAlUkC9Oc6a/+egbHnh9RfFQqUYKjqFZS62A3sba0phTZQ/mvodfMhjHAajYHgBP9uath/wDQePtwSHYOpZfb348XmeqEjstsotadMnmTvf7eoWgvstfeEToU= Message-ID: Date: Wed, 1 Mar 2006 14:57:05 +1100 From: "Michael Ellerman" To: "Darrick J. Wong" Subject: Re: [PATCH] leave APIC code inactive by default on i386 Cc: linux-kernel@vger.kernel.org, "Chris McDermott" In-Reply-To: <43D03AF0.3040703@us.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7BIT Content-Disposition: inline References: <43D03AF0.3040703@us.ibm.com> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1137 Lines: 26 On 1/20/06, Darrick J. Wong wrote: > Hi there, > > Some old i386 systems have flaky APIC hardware that doesn't always work > right. Right now, enabling the APIC code in Kconfig means that the APIC > code will try to activate the APICs unless 'noapic nolapic' are passed > to force them off. The attached patch provides a config option to > change that default to keep the APICs off unless specified otherwise, > disables get_smp_config if we are not initializing the local APIC, and > makes init_apic_mappings not init the IOAPICs if they are disabled. > Note that the current behavior is maintained if > CONFIG_X86_UP_APIC_DEFAULT_OFF=n. ... Did this hit the floor? It strikes me as a pretty good solution. This is pretty nasty for newbies installing distro kernels, they get some of the way through an install and then their machine just locks - not good PR. cheers - 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/