Hi, > https://launchpad.net/ubuntu/+source/cd-boot-images-amd64/7
Oh. This explains why there is still an invalid GPT in http://cdimage.ubuntu.com/daily-live/current/groovy-desktop-amd64.iso which i downloaded 2 days ago. Above change has at its end: + echo 'xorriso -as mkisofs [...] -append_partition 2 0xef images/boot/grub/efi.img [...] -e --interval:appended_partition_2:all:: [...] -part_like_isohybrid -isohybrid-gpt-basdat [...]' > xorriso-cmd.txt To blame for the invalid GPT is "-part_like_isohybrid -isohybrid-gpt- basdat". ------------------------------------------------------------------------ I downloaded a new groovy-desktop-amd64.iso and repacked it without these options: dd if=groovy-desktop-amd64.iso bs=512 count=1 \ of=groovy-desktop-amd64.mbr.img dd if=groovy-desktop-amd64.iso bs=512 skip=5715872 count=9952 \ of=groovy-desktop-amd64.efi.img xorriso -as mkisofs \ -o test.iso \ -J -joliet-long -l \ -b boot/grub/i386-pc/eltorito.img \ -no-emul-boot -boot-load-size 4 -boot-info-table --grub2-boot-info \ --grub2-mbr groovy-desktop-amd64.mbr.img \ -append_partition 2 0xef groovy-desktop-amd64.efi.img \ -eltorito-alt-boot \ -e --interval:appended_partition_2:all:: \ -no-emul-boot \ -partition_offset 16 -r \ /mnt/iso The numbers 5715872 and 9952 can be obtained by "/sbin/fdisk -l" or by xorriso inspection. This inspection iso=groovy-desktop-amd64.iso xorriso -indev "$iso" -report_system_area plain -report_el_torito plain yields for the downloaded ISO, iso=groovy-desktop-amd64.iso : Drive current: -indev 'groovy-desktop-amd64.iso' Media current: stdio file, overwriteable Media status : is written , is appendable Boot record : El Torito , MBR grub2-mbr cyl-align-off GPT Media summary: 1 session, 1431622 data blocks, 2796m data, 350g free Volume id : 'Ubuntu 20.10 amd64' System area options: 0x00004a00 System area summary: MBR grub2-mbr cyl-align-off GPT ISO image size/512 : 5726488 Partition offset : 16 MBR heads per cyl : 0 MBR secs per head : 0 MBR partition table: N Status Type Start Blocks MBR partition : 1 0x80 0xcd 64 5715808 MBR partition : 2 0x00 0xef 5715872 9952 GPT : N Info GPT disk GUID : 7631942462da4c4797ccfb75ca94a436 GPT entry array : 2 248 separated GPT lba range : 64 5726424 5726487 GPT partition name : 1 490053004f004800790062007200690064003100 GPT partname local : 1 ISOHybrid1 GPT partition GUID : 1 7631942462da4c4797cdfb75ca94a436 GPT type GUID : 1 a2a0d0ebe5b9334487c068b6b72699c7 GPT partition flags: 1 0x1000000000000001 GPT start and size : 1 5715872 9952 El Torito catalog : 678 1 El Torito cat path : /boot.catalog El Torito images : N Pltf B Emul Ld_seg Hdpt Ldsiz LBA El Torito boot img : 1 BIOS y none 0x0000 0x00 4 679 El Torito boot img : 2 UEFI y none 0x0000 0x00 9952 1428968 El Torito img path : 1 /boot/grub/i386-pc/eltorito.img El Torito img opts : 1 boot-info-table grub2-boot-info El Torito img blks : 2 2488 The new ISO yields: Drive current: -indev 'test.iso' Media current: stdio file, overwriteable Media status : is written , is appendable Boot record : El Torito , MBR grub2-mbr cyl-align-off Media summary: 1 session, 1431606 data blocks, 2796m data, 347g free Volume id : 'ISOIMAGE' System area options: 0x00004a00 System area summary: MBR grub2-mbr cyl-align-off ISO image size/512 : 5726424 Partition offset : 16 MBR heads per cyl : 0 MBR secs per head : 0 MBR partition table: N Status Type Start Blocks MBR partition : 1 0x80 0xcd 64 5715808 MBR partition : 2 0x00 0xef 5715872 9952 El Torito catalog : 678 1 El Torito cat path : /boot.catalog El Torito images : N Pltf B Emul Ld_seg Hdpt Ldsiz LBA El Torito boot img : 1 BIOS y none 0x0000 0x00 4 679 El Torito boot img : 2 UEFI y none 0x0000 0x00 9952 1428968 El Torito img path : 1 /boot/grub/i386-pc/eltorito.img El Torito img opts : 1 boot-info-table grub2-boot-info El Torito img blks : 2 2488 which is what i proposed to debian-cd and debian-live a year ago. The GPT of the original ISO is not valid because the MBR partition table has two partitions. GPT would be valid only if there is a single MBR partition of type 0xee, which covers the range from LBA 1 up to the ISO's end. Have a nice day :) Thomas -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1895131 Title: Groovy Desktop *BREAKS* the most common method of creating UEFI bootable drives for Ubuntu installation To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/casper/+bug/1895131/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
