From owner-freebsd-arch@FreeBSD.ORG Wed Mar 23 17:50:46 2011 Return-Path: Delivered-To: freebsd-arch@FreeBSD.ORG Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 04EA4106564A; Wed, 23 Mar 2011 17:50:46 +0000 (UTC) (envelope-from olli@lurza.secnetix.de) Received: from lurza.secnetix.de (lurza.secnetix.de [IPv6:2a01:170:102f::2]) by mx1.freebsd.org (Postfix) with ESMTP id 734178FC0C; Wed, 23 Mar 2011 17:50:45 +0000 (UTC) Received: from lurza.secnetix.de (localhost [127.0.0.1]) by lurza.secnetix.de (8.14.3/8.14.3) with ESMTP id p2NHoSk2009827; Wed, 23 Mar 2011 18:50:43 +0100 (CET) (envelope-from oliver.fromme@secnetix.de) Received: (from olli@localhost) by lurza.secnetix.de (8.14.3/8.14.3/Submit) id p2NHoSF6009826; Wed, 23 Mar 2011 18:50:28 +0100 (CET) (envelope-from olli) Date: Wed, 23 Mar 2011 18:50:28 +0100 (CET) Message-Id: <201103231750.p2NHoSF6009826@lurza.secnetix.de> From: Oliver Fromme To: freebsd-arch@FreeBSD.ORG, arundel@FreeBSD.ORG, bz@FreeBSD.ORG In-Reply-To: <20110323171443.GA59972@freebsd.org> X-Newsgroups: list.freebsd-arch User-Agent: tin/1.8.3-20070201 ("Scotasay") (UNIX) (FreeBSD/6.4-PRERELEASE-20080904 (i386)) MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8bit X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.3.5 (lurza.secnetix.de [127.0.0.1]); Wed, 23 Mar 2011 18:50:44 +0100 (CET) Cc: Subject: Re: kernel memory checks on boot vs. boot time X-BeenThere: freebsd-arch@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussion related to FreeBSD architecture List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 23 Mar 2011 17:50:46 -0000 Alexander Best wrote: > just as a side note: booting a kernel directly from boot stage 2 is broken on > amd64. :( so there's no way around using the boot loader, which will cost extra > time (even with autoboot_delay=0). > > so was the adbility to boot a kernel directly from boot2 abandoned? i heard > reports it still works under i386. dunno about the other archs. The loader checks the type of the kernel binary (i386 vs amd64). In case of amd64, it enables "long mode", among other things. This is required for amd64, because the kernel expects to be started in long mode. boot2 doesn't do that, so you can't start an amd64 kernel directly from boot2. In theory you could write a specialized amd64 variant of boot2 that prepares the system for starting an amd64 kernel directly. Whether there's enough space for that in boot2 (8 KB) and whether it's worth the effort, I don't know. To be honest, I don't think that loader takes so much time. When you set autoboot_delay="-1" and beastie_disable="YES", the time spent in loader is negligible. (I'm assuming that you also set BOOTWAIT=0 in make.conf, so boot2 doesn't wait for a keypress either. I think the default is to wait 3 seconds.) Best regards Oliver -- Oliver Fromme, secnetix GmbH & Co. KG, Marktplatz 29, 85567 Grafing b. M. Handelsregister: Registergericht Muenchen, HRA 74606, Geschäftsfuehrung: secnetix Verwaltungsgesellsch. mbH, Handelsregister: Registergericht Mün- chen, HRB 125758, Geschäftsführer: Maik Bachmann, Olaf Erb, Ralf Gebhart FreeBSD-Dienstleistungen, -Produkte und mehr: http://www.secnetix.de/bsd "[...] one observation we can make here is that Python makes an excellent pseudocoding language, with the wonderful attribute that it can actually be executed." -- Bruce Eckel