512b vs. 2048b problems on IBM Power LPAR (Debian/PPC)

[Frank Fegert]

Hello all,

i'm having some trouble with the d-i (squeeze and wheezy [1], the lenny
d-i used to work though) on IBM Power LPARs. On the yaboot installer
step the d-i breaks with:
  [!!] Install yaboot on a hard disk
  No bootstrap partition found
  No hard disks were found which have an "Apple_Bootstrap" partition.
  You must create an 819200-byte partition with type "Apple_Bootstrap".

We've (see Debian Bug #350372, last entries) tracked this down to the
call of "/usr/lib/partconf/find-partitions --flag prep" which drops
out with the error:
  ~ # /usr/lib/partconf/find-partitions --flag prep
  Warning: The driver descriptor says the physical block size is 512 bytes,
  but Linux says it is 2048 bytes.

  A bug has been detected in GNU Parted.  Refer to the web site of
  parted http://www.gnu.org/software/parted/parted.html for more
  information of what could be useful for bug submitting!  Please
  email a bug report to address@hidden containing at least the
  version (2.3) and the following message:  Assertion (disk != NULL)
  at ../../libparted/disk.c:1548 in function ped_disk_next_partition()
  failed.  Aborted

The setup is SAN-based disk -> dual VIOS -> LPAR (sda and sdb are one
path for each VIOS to the same physical disk). The partition table looks
like this:
  ~ # parted /dev/sda unit s print free
  Model: AIX VDASD (scsi)
  Disk /dev/sda: 75497472s
  Sector size (logical/physical): 512B/512B
  Partition Table: msdos
  Number  Start      End        Size       Type     File system  Flags
          63s        2047s      1985s               Free Space
   1      2048s      16383s     14336s     primary               boot, prep
   2      16384s     3921919s   3905536s   primary  ext4
   3      3921920s   75495423s  71573504s  primary               lvm
          75495424s  75497471s  2048s               Free Space

Can someone please shed some light on as to why this is happening on
Debian versions later then lenny? And/or can someone please assist me
in further debugging and possibly resolving this issue?

Thanks & best regards,

    Frank Fegert


[1] "Debian GNU/Linux testing _Wheezy_ - Official Snapshot powerpc NETINST 
Binary-1 20130112-15:23"

debian-wheezy-installer_20130112.tar.gz
Description: Binary data