From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1MHGKm-0001wq-Ma for qemu-devel@nongnu.org; Thu, 18 Jun 2009 08:03:12 -0400 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1MHGKh-0001vM-Nm for qemu-devel@nongnu.org; Thu, 18 Jun 2009 08:03:12 -0400 Received: from [199.232.76.173] (port=57944 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1MHGKg-0001v1-T7 for qemu-devel@nongnu.org; Thu, 18 Jun 2009 08:03:07 -0400 Received: from mx2.redhat.com ([66.187.237.31]:40365) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1MHGKg-0000Ac-9M for qemu-devel@nongnu.org; Thu, 18 Jun 2009 08:03:06 -0400 Message-ID: <4A3A2CB2.3090609@redhat.com> Date: Thu, 18 Jun 2009 14:01:54 +0200 From: Kevin Wolf MIME-Version: 1.0 Subject: Re: [Qemu-devel] [PATCH 0/4] Add multiboot support (x86) v2 References: <1010895772-BeMail@laptop> In-Reply-To: <1010895772-BeMail@laptop> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: =?UTF-8?B?RnJhbsOnb2lzIFJldm9s?= Cc: rene@exactcode.de, agraf@suse.de, qemu-devel@nongnu.org Fran=C3=A7ois Revol schrieb: >> Why would an OS want to parse multiboot structures but not implement >> proper multiboot support? I mean, this really isn't anything >> complicated. When you have enabled it to understand multiboot=20 >> structures >> you are only missing a handful of bytes for the multiboot header. >> >> What is it that you need to do differently for Haiku? >=20 > Because Haiku has its own second stage loader, which requires the BIOS=20 > to locate the kernel and module in a BFS partition which grub doesn't=20 > implement btw. That makes sense on real hardware, of course. But for -kernel you don't need a file system to read the kernel from. I'm not talking about replacing the existing loader, but just about adding support for multiboot as an additional option. Don't know how the Haiku boot process works though, so maybe I'm completely wrong. > It also handles PM switching by itself. > Haiku might also use the BIOS for other stuff, like VESA mode=20 > switching, so I'd need to make sure all calls aren't strictly required. In theory you could switch back to Real Mode when starting through multiboot and then continue as with a normal boot. Admittedly, doesn't sound exactly nice, but should be doable... Kevin