From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from list by lists.gnu.org with archive (Exim 4.71) id 1VcgP2-0005QC-OZ for mharc-grub-devel@gnu.org; Sat, 02 Nov 2013 14:58:32 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:49725) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VcgOt-0005P3-Qq for grub-devel@gnu.org; Sat, 02 Nov 2013 14:58:31 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1VcgOm-0005fO-H2 for grub-devel@gnu.org; Sat, 02 Nov 2013 14:58:23 -0400 Received: from mout.gmx.net ([212.227.15.19]:60491) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VcgOm-0005f1-7h for grub-devel@gnu.org; Sat, 02 Nov 2013 14:58:16 -0400 Received: from scdbackup.webframe.org ([87.167.181.135]) by mail.gmx.com (mrgmx001) with ESMTP (Nemesis) id 0M3iU5-1Vu4gx0r3p-00rGYF for ; Sat, 02 Nov 2013 19:58:14 +0100 Date: Sat, 02 Nov 2013 19:57:18 +0100 From: "Thomas Schmitt" To: grub-devel@gnu.org Subject: How important is the MBR partition offset of grub-mkrescue ? Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Message-Id: <10533651190322788149@scdbackup.webframe.org> X-Provags-ID: V03:K0:hDHDg1blgqp097E1b6t6S/fnN3sbkSvNYrKXSRqxFUdAwLsY18a vJmKvslLMMzXvAT1te8+pArsZvNBSgDKuUoZC0Oy2m/EjLvjBUlPDQNm3/uBWWLNFKRQnnR q7DoA33OuQ6uwQ2es2FKV1Gpt8leX/q6hRIsULhozNKwoWXL5GXmolJK3S+YzSot5J5G+Nd fGiXx9iCpK/6lMRHUvZGg== X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.4.x-2.6.x [generic] X-Received-From: 212.227.15.19 X-BeenThere: grub-devel@gnu.org X-Mailman-Version: 2.1.14 Precedence: list Reply-To: The development of GNU GRUB List-Id: The development of GNU GRUB List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 02 Nov 2013 18:58:31 -0000 Hi, i stumbled over a problem in the handling of grub-mkrescue images on USB stick by Linux in /dev/disk/by-label. The first MBR partition begins at 512-LBA 1 and thus is not mountable as ISO image. I understand this is intentional. ISO filesystems have a label (Volume Id) which gets used for auto-mounting and shows up in modern Linuxes as symbolic link in directory /dev/disk/by-label. But Linux (or its udev) insists in linking to /dev/sdX1 rather than to /dev/sdX, where the ISO filesystem is mountable. So this link cannot be used for mounting the ISO. I hate automounters, but /dev/disk/by-label is also a good way for a booting system to find its own filesystem from where it stems. ---------------------------------------------------------- Is a workaround known on Linux side ? (E.g. is it a known bug in udev configurations which can be fixed ?) How important ist the partition start at LBA 1 in comparison to this obvious drawback of grub-mkrescue images on Linux ? (Start at LBA 0 solves the problem but makes the MBR part of the first partition. I understand this is undesirable somehow.) Actually i wanted to show a system packager how to use ./by-label instead of test-mounting all files in /proc/partitions. Are there other methods which one could use in the Linux initial RAM disk to find the USB stick from where GRUB2 did boot ? Have a nice day :) Thomas