Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964880AbVKOQaP (ORCPT ); Tue, 15 Nov 2005 11:30:15 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S964887AbVKOQaP (ORCPT ); Tue, 15 Nov 2005 11:30:15 -0500 Received: from terminus.zytor.com ([192.83.249.54]:39810 "EHLO terminus.zytor.com") by vger.kernel.org with ESMTP id S964880AbVKOQaN (ORCPT ); Tue, 15 Nov 2005 11:30:13 -0500 Message-ID: <437A0CBA.3050302@zytor.com> Date: Tue, 15 Nov 2005 08:28:42 -0800 From: "H. Peter Anvin" User-Agent: Mozilla Thunderbird 1.0.7-1.1.fc4 (X11/20050929) X-Accept-Language: en-us, en MIME-Version: 1.0 To: Dave Jones CC: Arjan van de Ven , Zachary Amsden , Gerd Knorr , Linus Torvalds , Pavel Machek , Andrew Morton , Linux Kernel Mailing List , Zwane Mwaikambo , Pratap Subrahmanyam , Christopher Li , "Eric W. Biederman" , Ingo Molnar Subject: Re: [PATCH 1/10] Cr4 is valid on some 486s References: <4378A7F3.9070704@suse.de> <4379ECC1.20005@suse.de> <437A0649.7010702@suse.de> <437A0710.4020107@vmware.com> <1132070764.2822.27.camel@laptopd505.fenrus.org> <20051115161041.GA1749@redhat.com> <437A0965.7020909@zytor.com> <20051115161949.GC1749@redhat.com> In-Reply-To: <20051115161949.GC1749@redhat.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 564 Lines: 17 Dave Jones wrote: > > > > If you have CPU hotplug enabled, you can run SMP code! > > Sure, but if you boot with 1 CPU, spinlocks get nop'd to emulate UP, > and on a 'installed a new cpu' hotplug event, they all come back. > The point that you don't nop if you have hotplug enabled (which is not the norm.) -hpa - 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/