From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with archive (Exim 4.43) id 1Gp2Lo-0005Nz-44 for mharc-grub-devel@gnu.org; Tue, 28 Nov 2006 07:46:16 -0500 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1Gp2Lm-0005MQ-R3 for grub-devel@gnu.org; Tue, 28 Nov 2006 07:46:14 -0500 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1Gp2Lk-0005Ki-Jj for grub-devel@gnu.org; Tue, 28 Nov 2006 07:46:14 -0500 Received: from [199.232.76.173] (helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1Gp2Lk-0005Kf-Eo for grub-devel@gnu.org; Tue, 28 Nov 2006 07:46:12 -0500 Received: from [143.182.124.21] (helo=mga03.intel.com) by monty-python.gnu.org with esmtp (Exim 4.52) id 1Gp2Lk-0003QO-CJ for grub-devel@gnu.org; Tue, 28 Nov 2006 07:46:12 -0500 Received: from azsmga001.ch.intel.com ([10.2.17.19]) by mga03.intel.com with ESMTP; 28 Nov 2006 04:46:10 -0800 Received: from unknown (HELO [172.16.96.242]) ([172.16.96.242]) by azsmga001.ch.intel.com with ESMTP; 28 Nov 2006 04:46:10 -0800 X-ExtLoop1: 1 X-IronPort-AV: i="4.09,469,1157353200"; d="scan'208"; a="151194162:sNHT18132037" Message-ID: <456C2F8C.1040709@intel.com> Date: Tue, 28 Nov 2006 20:46:04 +0800 From: "bibo,mao" User-Agent: Thunderbird 1.5.0.8 (Windows/20061025) MIME-Version: 1.0 To: The development of GRUB 2 References: <200611281235.48809.okuji@enbug.org> In-Reply-To: <200611281235.48809.okuji@enbug.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: multiboot2: variable data size X-BeenThere: grub-devel@gnu.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: The development of GRUB 2 List-Id: The development of GRUB 2 List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 28 Nov 2006 12:46:15 -0000 Yoshinori K. Okuji wrote: > On Tuesday 28 November 2006 10:29, Johan Rydberg wrote: > > "Yoshinori K. Okuji" writes: > > > On Saturday 25 November 2006 04:33, Hollis Blanchard wrote: > > >> That's exactly the point: there will be no difference. Both > > >> architectures will use 64-bit types. > > > > > > No. Both should use 32-bit, because GRUB transfers control in 32-bit > > > mode. Passing 64-bit addresses would be useless in this case. Note that > > > the memory map information is 64-bit even in the previous version of > > > Multiboot Spec. > > > > That will not be true for x86_64-efi, which will have to run in long > > mode. > > Oh, sorry. I meant "x86_64-pc" in the previous message. I just omitted "pc". > When the firmware is different, it is feasible to make a different spec, > but... > > But is it true that EFI starts with 64-bit mode? Where is it defined? In UEFI? > Could you give me a pointer? > yes, x84_64EFI starts with 64-bit long mode and page enabled(virtual address equals physical address) if it is x86_64 efi bios, it is defined in section 2.3.4 of UEFI Specification Version 2.0. If kernel image is bzImage, x64 efi bootloader need switch to 32 bit protect mode(or real mode) from 64 bit long mode, and if kernel image is gzipped/plain format, efi bootloader can directly jump to 64-bit kernel entry address without mode switch. thanks bibo,mao