Hi, i wonder why my mail of Thu, 29 Jan 2015 08:14:08 +0100 does not show up in debian-cd mailing list. It reported about a preliminary experiment with amd64 mini.iso. Meanwhile it is quite outdated by my new experiments with an arm64 ISO.
------------------------------------------------------------- I downloaded http://cloudfront.debian.net/cdimage/jessie_di_beta_2/arm64/iso-cd/debian-jessie-DI-b2-arm64-netinst.iso of 2014-10-03. Inspection yields: Volume id : 'Debian jessie-DI-b2 arm64 1' El Torito catalog : 832 1 El Torito cat path : /boot.catalog El Torito images : N Pltf B Emul Ld_seg Hdpt Ldsiz LBA El Torito boot img : 1 UEFI y none 0x0000 0x00 768 833 El Torito img path : 1 /boot/grub/efi.img xorriso : NOTE : No System Area was loaded This looks like amd64 mini.iso without the BIOS stuff. After reading its /.disk/mkisofs, i re-pack it by # A dummy MBR template as substitute for isohdpfx.bin dd if=/dev/zero bs=432 count=1 of=null.mbr mount -o loop debian-jessie-DI-b2-arm64-netinst.iso /mnt/iso xorriso -as mkisofs \ -V 'Debian jessie-DI-b2 arm64 1' \ -r -o test.iso -J -joliet-long -cache-inodes \ -isohybrid-mbr null.mbr \ -e boot/grub/efi.img -no-emul-boot -isohybrid-gpt-basdat \ /mnt/iso Omitted options: all Jigdo options -eltorito-alt-boot is a separator which is needed only if already a boot image was defined by -b, -e, or alike Added options: -isohybrid-gpt-basdat works only if -isohybrid-mbr is present -isohybrid-mbr gets as input the dummy MBR template. So SYSLINUX is not needed. The result shows nested partitions in MBR and GPT. This is the mjg layout, which partition editors dislike heavily but seems to work well in the amd64 netinst ISOs. It offers three entry points for booting: El Torito, MBR, GPT. ------------------------------------------------------------------------ El Torito catalog : 832 1 El Torito cat path : /boot.catalog El Torito images : N Pltf B Emul Ld_seg Hdpt Ldsiz LBA El Torito boot img : 1 UEFI y none 0x0000 0x00 768 833 El Torito img path : 1 /boot/grub/efi.img System area options: 0x00000900 System area summary: MBR cyl-align-on GPT ISO image size/512 : 262144 Partition offset : 0 MBR heads per cyl : 64 MBR secs per head : 32 MBR partition table: N Status Type Start Blocks MBR partition : 1 0x80 0x00 0 262144 MBR partition : 2 0x00 0xef 3332 768 MBR partition path : 2 /boot/grub/efi.img GPT : N Info GPT disk GUID : 8822d6a0aadcde40a8afcd569dc28802 GPT entry array : 2 248 overlapping GPT lba range : 64 262080 262143 GPT partition name : 1 490053004f00480079006200720069006400 GPT partname local : 1 ISOHybrid GPT partition GUID : 1 8822d6a0aadcde40a8adcd569dc28802 GPT type GUID : 1 a2a0d0ebe5b9334487c068b6b72699c7 GPT partition flags: 1 0x1000000000000001 GPT start and size : 1 0 262080 GPT partition name : 2 490053004f004800790062007200690064003100 GPT partname local : 2 ISOHybrid1 GPT partition GUID : 2 8822d6a0aadcde40a8accd569dc28802 GPT type GUID : 2 a2a0d0ebe5b9334487c068b6b72699c7 GPT partition flags: 2 0x1000000000000001 GPT start and size : 2 3332 768 GPT partition path : 2 /boot/grub/efi.img ------------------------------------------------------------------------ Of course it is odd to use ISOLINUX related xorriso commands with pure GRUB2 boot equipment. Especially since Vladimir Serbinenko puts much emphasis on a neat partition table. Let's try an option which was introduced for grub-mkrescue xorriso -as mkisofs \ -V 'Debian jessie-DI-b2 arm64 1' \ -r -o test.iso -J -joliet-long -cache-inodes \ -efi-boot-part --efi-boot-image \ -e boot/grub/efi.img -no-emul-boot \ /mnt/iso Added options: -efi-boot-part with special argument "--efi-boot-image" marks the first EFI El Torito boot image as partition in GPT. Only a "protective MBR" emerges, which complies to GPT specs. (Other than a multi-partition MBR.) This yields a more conventional partition layout. The range of the ISO filesystem is protected by the MBR partition and by three GPT partitions, of which the middle one points to the EFI boot filesystem in /boot/grub/efi.img. Only two boot entry points are provided: El Torito and GPT. ------------------------------------------------------------------------ El Torito catalog : 1024 1 El Torito cat path : /boot.catalog El Torito images : N Pltf B Emul Ld_seg Hdpt Ldsiz LBA El Torito boot img : 1 UEFI y none 0x0000 0x00 768 831 El Torito img path : 1 /boot/grub/efi.img System area options: 0x00000201 System area summary: MBR protective-msdos-label cyl-align-off GPT ISO image size/512 : 260484 Partition offset : 0 MBR heads per cyl : 64 MBR secs per head : 32 MBR partition table: N Status Type Start Blocks MBR partition : 1 0x00 0xee 1 260483 GPT : N Info GPT disk GUID : 307e73f26c8c7b4a9dd739bd9e5991fe GPT entry array : 2 248 separated GPT lba range : 64 260420 260483 GPT partition name : 1 4700610070003000 GPT partname local : 1 Gap0 GPT partition GUID : 1 307e73f26c8c7b4a9dd439bd9e5991fe GPT type GUID : 1 a2a0d0ebe5b9334487c068b6b72699c7 GPT partition flags: 1 0x1000000000000001 GPT start and size : 1 64 3260 GPT partition name : 2 450046004900200062006f006f007400200070006100720074006900740069006f006e00 GPT partname local : 2 EFI boot partition GPT partition GUID : 2 307e73f26c8c7b4a9dd539bd9e5991fe GPT type GUID : 2 28732ac11ff8d211ba4b00a0c93ec93b GPT partition flags: 2 0x1000000000000001 GPT start and size : 2 3324 768 GPT partition path : 2 /boot/grub/efi.img GPT partition name : 3 4700610070003100 GPT partname local : 3 Gap1 GPT partition GUID : 3 307e73f26c8c7b4a9dd639bd9e5991fe GPT type GUID : 3 a2a0d0ebe5b9334487c068b6b72699c7 GPT partition flags: 3 0x1000000000000001 GPT start and size : 3 4092 256328 ------------------------------------------------------------------------ One should consider to use grub-mkrescue for pure GRUB2 boot equipment. It is well coordinated with GRUB2 but rarely seen as producer of distro ISOs. Regrettably there is a small unintended CLI compatibility problem between the old bash script and the new C program: - The script needs argument "--" only to throw xorriso out of its mkisofs emulation. (There is few reason to do this.) - The C program needs argument "--" to end its own option list and to start the list of additional xorriso -as mkisofs options. (A second "--" would end mkisofs emulation of xorriso.) The list of additional options would contain all xorriso options which do not directly deal with boot aspects or the output ISO path. I.e. the many Jigdo options, -r -V -J -joliet-long -cache-inodes CD1. But not -o ... -eltorito-alt-boot -e boot/grub/efi.img -no-emul-boot Depending on its content, "boot1" may be needed or not. All boot files up to the start of the Linux kernel are produced by grub-mkrescue. Vladimir stated that the CLI change was unintentional. But he did not yet decide whether to fix it by a proposal of Andrei Borzenkov, or by a proposal of mine, or by some other idea. See: http://lists.gnu.org/archive/html/grub-devel/2014-11/msg00076.html http://lists.gnu.org/archive/html/grub-devel/2014-11/msg00082.html http://lists.gnu.org/archive/html/grub-devel/2014-11/msg00083.html which are late follow-ups of http://lists.gnu.org/archive/html/grub-devel/2014-09/msg00067.html (Maybe if users show up and encourage a swift decision ...) Well, the user just has to know which grub-mkrescue variant is at hand and thus insert the "--" argument or not. Either grub-mkrescue or xorriso will protest loudly if the wrong variant was assumed. Have a nice day :) Thomas -- To UNSUBSCRIBE, email to debian-arm-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org Archive: https://lists.debian.org/20912544154953578...@scdbackup.webframe.org
