Re: [Bug-xorriso] Test Proposal for [bug #46716] Protective MBR partition is not marked as bootable

[Thomas Schmitt]

Hi,

Andrei Borzenkov wrote:
> Try access ESP content.

Err ... looking up manual ... you mean this ?
With ISO without -hfsplus :

  qemu ... -bios .../OVMF.fd -cdrom ...iso

  grub> ls (cd0,msdos2)/
  error: unknown filesystem.

In contrast to

  qemu ... -bios .../OVMF.fd -hda ...iso

  grub> ls (hd0,msdos2)/
  efi/ Nvars

Do you have a theory why this happens ?
(Beyond the simple fact that i did not obey to Vladimir's
 prescriptions.)

------------------------------------------------------------

I see with -cdrom of the ISO without HFS+ and APM:

  grub> ls (cd0)
  ...
  Total size 18990KiB
  grub> ls (cd0,msdos2)
         ... Partition start at 64440KiB - Total size 11520KiB

whereas xorriso sees

  MBR partition table:   N Status  Type        Start       Blocks
  MBR partition      :   1   0x00  0x83            0        32220
  MBR partition      :   2   0x00  0xef        32220         5760

For some reason the perception of GRUB2 is too large by a factor
of two.

Lets call fdisk -lu as umpire (too old to take sides):

  Device  Boot Start   End Sectors  Size Id Type
  ...iso1          0 32219   32220 15.8M 83 Linux
  ...iso2      32220 37979    5760  2.8M ef EFI (FAT-12/16/32)

So either GRUB2 or OVMF is wrong, i'd say ... noobishly. {:)

----------------------------------------------------------------

With Alexander's grub-mkrescue original ISO:

  grub > ls (cd0,gpt2)
       ... Partition start at 168KiB - Total size 2880KiB

xorriso sees

  GPT start and size :   2  336  5760
  GPT partition path :   2  /efi.img

fdisk ain't that old, after all:

  Disklabel type: gpt
  ...
  Device  Start   End Sectors  Size Type
  ...iso2   336  6095    5760  2.8M EFI System


Have a nice day :)

Thomas