Comment 1 for bug 1022511

I was intending to look at this at some stage.
Configuration is a good thing here to support various devices and security standards.
Some notes I have for various options:

none
  Don't bother, or leave to lower layers (see discard)
zero
  dd bs=1M if=/dev/zero
shred
  # doesn't use /dev/urandom by default as very slow and overkill
  # uses 3 passes by default
  # does not yet support DoD 5220 rules
  # does not yet support ATA secure erase
discard
  # benefits on SSDs to return blocks to pool and efficiently erase
  # some devices don's zero on discard. See /sys/block/$dev/queue/discard_zeroes_data
  # lvm supports directly since 2.02.85 (04/2011) with issue_discards=1 in /etc/lvm/lvm.conf
  # manual trim call with hdparm --trim-sector-ranges. That's a bit awkward though...
  # ... must look into adding simple support to some command (fstrim, truncate,shred?)
  # Note mkfs.* generally do a trim of the device first anyway

I'd not considered a partial overwrite of the start of the device,
as discussed in the referenced email thread. Does that provide
any functional benefit?