From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with archive (Exim 4.43) id 1Kapjm-00070y-Nt for mharc-grub-devel@gnu.org; Wed, 03 Sep 2008 06:37:22 -0400 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1Kapjh-0006zu-S7 for grub-devel@gnu.org; Wed, 03 Sep 2008 06:37:18 -0400 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1Kapje-0006yr-PY for grub-devel@gnu.org; Wed, 03 Sep 2008 06:37:16 -0400 Received: from [199.232.76.173] (port=39107 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1Kapje-0006yd-4g for grub-devel@gnu.org; Wed, 03 Sep 2008 06:37:14 -0400 Received: from extu-mxob-2.symantec.com ([216.10.194.135]:55017) by monty-python.gnu.org with esmtps (TLS-1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.60) (envelope-from ) id 1Kapjd-0008TO-LP for grub-devel@gnu.org; Wed, 03 Sep 2008 06:37:14 -0400 Received: from tus1opsmtapin01.ges.symantec.com (tus1opsmtapin01.ges.symantec.com [192.168.214.43]) by extu-mxob-2.symantec.com (8.14.1/8.14.1) with ESMTP id m83AaubK026301 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO) for ; Wed, 3 Sep 2008 03:36:56 -0700 Received: from reserved-155-64-230-20.ges.symantec.com ([155.64.230.20] helo=TUS1XCHECNPIN03.enterprise.veritas.com) by tus1opsmtapin01.ges.symantec.com with esmtp (Exim 4.67) (envelope-from ) id 1KapjM-000892-02 for grub-devel@gnu.org; Wed, 03 Sep 2008 03:36:56 -0700 Received: from PUNAXCHECNPIN01.enterprise.veritas.com ([10.217.161.21]) by TUS1XCHECNPIN03.enterprise.veritas.com with Microsoft SMTPSVC(6.0.3790.1830); Wed, 3 Sep 2008 03:36:56 -0700 Received: from [10.212.96.224] ([10.212.96.224]) by PUNAXCHECNPIN01.enterprise.veritas.com with Microsoft SMTPSVC(6.0.3790.1433); Wed, 3 Sep 2008 16:06:49 +0530 Message-ID: <48BE6ACD.7090607@symantec.com> Date: Wed, 03 Sep 2008 16:15:33 +0530 From: BVK Chaitanya User-Agent: Mozilla-Thunderbird 2.0.0.14 (X11/20080509) MIME-Version: 1.0 To: The development of GRUB 2 References: <20080830124058.GI16775@thorin> In-Reply-To: <20080830124058.GI16775@thorin> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-OriginalArrivalTime: 03 Sep 2008 10:36:49.0412 (UTC) FILETIME=[F8AAD440:01C90DB0] X-detected-kernel: by monty-python.gnu.org: Linux 2.4-2.6 Subject: Re: Idea: Move kernel to upper memory 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: Wed, 03 Sep 2008 10:37:18 -0000 Hi, What is the conclusion of this thread? is this idea still explored? Robert Millan wrote: > > The first concern that comes to mind is how would GRUB coexist with the > payload area which precisely starts at 0x100000. But I expect we'd face > many unexpected issues. > Does this mean, GRUB needs to fit within 1MB limit when all its modules are loaded? More clearly, are there any limits on where (and how many) grub modules can be dynamically loaded currently? Since payload(s) needs to be present at their precise positions only after the boot command, we can always deterministically /schedule/ memmove operation to be executed as part of boot command. Since boot command is the last command executed by GRUB (correct me if not), we can overwrite any GRUB code/data at that point. This also needs boot command to exist in low memory. The main advantage i see here is that it removes any arbitrary limits on number of modules or their placement, if at all limits exists. thanks, -- bvk-chaitanya