Re: [Bug-xorriso] xorriso and Fedora livecd-tools

[Thomas Schmitt]

Hi,

are there any modern Fedora ISOs for PPC ?


To learn more about Fedora for PPC i went to
  https://fedoraproject.org/wiki/Architectures/PowerPC
which says that only 64 bit machines are supported and sends me to
  https://alt.fedoraproject.org/alt/
which says
  "AArch64 “Server Base System Architecture” (SBSA)"
So this gives me Fedora images for ARM64, not for PowerPC.
I downloaded
  Fedora-Server-netinst-aarch64-27-1.6.iso

It boots by EFI from CD/DVD/BD (and by OVMF from any virtual medium).
It does not expose a partition table for EFI from USB stick.
We could fix that by an appended partition and pointing El Torito to it.


The last ISO for "ppc" which i can find in
  https://archives.fedoraproject.org/pub/archive/fedora/linux/releases/
is with release 12, e.g.
  
https://archives.fedoraproject.org/pub/archive/fedora/linux/releases/12/Fedora/ppc/iso/Fedora-12-ppc-netinst.iso

It contains MBR partitions of type 0x96 (for CHRP) and 0x41 (PReP):

  MBR partition table:   N Status  Type        Start       Blocks
  MBR partition      :   1   0x80  0x96            0       542676
  MBR partition      :   2   0x80  0x41       406152        56332
  MBR partition path :   2  /images/netboot/ppc32.img

About PReP i have exactly one sentence from Vladimir Serbinenko:
"PReP boots via a MBR partition containing only raw ELF and having type 0x41."

Then there is an Apple Partition Map with a single partiton:
  APM                :   N  Info
  APM block size     :      512
  APM partition name :   1  PBOOT
  APM partition type :   1  Apple_HFS
  APM start and size :   1  16  542660
I assume this stems from mkisofs option -hfs.

This APM and HFS cannot be reproduced by xorriso. But PReP and CHRP are less
of a problem.
Regrettably my boot equipment proposer miserably failed with that ISO.
I will need to enhance it.

With manual testes i found out that currently xorriso refuses to combine
CHRP and PReP the mkisofs way:

  $ xorriso -as mkisofs -o /dvdbuffer/test.iso -V 'PBOOT'
    -chrp-boot-part
    -prep-boot-part /mnt/iso/images/netboot/ppc32.img
    /mnt/iso
  ...
  libisofs: FAILURE : Overlapping MBR partition entries requested

This not-so-mkisofs-ish run

  $ xorriso -as mkisofs -o /dvdbuffer/test.iso -V 'PBOOT'
    -chrp-boot-part
    -append_partition 2 0x41 /mnt/iso/images/netboot/ppc32.img
    /mnt/iso

yields MBR partitions for PReP and CHRP

  MBR partition table:   N Status  Type        Start       Blocks
  MBR partition      :   1   0x80  0x96            0       526364
  MBR partition      :   2   0x00  0x41       526364        56332

One would have to test whether this boots somewhere. The original is 8 years
old.


Have a nice day :)

Thomas