From owner-freebsd-hackers@FreeBSD.ORG Tue May 15 17:03:29 2012 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 49037106566C for ; Tue, 15 May 2012 17:03:28 +0000 (UTC) (envelope-from jhb@freebsd.org) Received: from bigwig.baldwin.cx (bigknife-pt.tunnel.tserv9.chi1.ipv6.he.net [IPv6:2001:470:1f10:75::2]) by mx1.freebsd.org (Postfix) with ESMTP id 1E36E8FC12 for ; Tue, 15 May 2012 17:03:28 +0000 (UTC) Received: from jhbbsd.localnet (unknown [209.249.190.124]) by bigwig.baldwin.cx (Postfix) with ESMTPSA id 8684BB911; Tue, 15 May 2012 13:03:27 -0400 (EDT) From: John Baldwin To: freebsd-hackers@freebsd.org Date: Tue, 15 May 2012 11:38:43 -0400 User-Agent: KMail/1.13.5 (FreeBSD/8.2-CBSD-20110714-p13; KDE/4.5.5; amd64; ; ) References: <4FA95960.7090908@shadowsun.net> <4FB17B85.9080701@shadowsun.net> In-Reply-To: MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <201205151138.43864.jhb@freebsd.org> X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.2.7 (bigwig.baldwin.cx); Tue, 15 May 2012 13:03:27 -0400 (EDT) Cc: Eric McCorkle Subject: Re: GSoC Project: EFI on amd64/i386 X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 15 May 2012 17:03:29 -0000 On Tuesday, May 15, 2012 4:00:44 am Michael Reifenberger wrote: > On Mon, 14 May 2012, Eric McCorkle wrote: > ... > > If I understand things correctly, boot2 handles the switch to > > protected mode (as well as enabling A20), both loader(8) and the > > kernel begin their execution in a protected mode environment. Can I > > get an absolute confirmation on this? Obviously if this is not the > > case, then there will need to be another (protected mode) entry point > > into the kernel. > > > > No. > *boot* and *loader should be the same on X32 and AMD64. > The kernel seems to switch to long mode in /sys/amd64/amd64/mpboot.S No. That is only for AP startup. The loader switches to long mode for an amd64 kernel before it starts the kernel. For i386, boot2 and the loader both start the kernel while running in flat 32-bit protected mode (so no paging). -- John Baldwin