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[Launchpad Bug Tracker <1097042@xxxxxxxxxxxxxxxxxx>]

[Expired for linux (Ubuntu) because there has been no activity for 60
days.]

** Changed in: linux (Ubuntu)
       Status: Incomplete => Expired

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https://bugs.launchpad.net/bugs/1097042

Title:
  Risk of filesystem corruption with ext3 in lucid

Status in “linux” package in Ubuntu:
  Expired

Bug description:
  On my system, a default ext3 mount (no fstab entry) results in:
  $ cat /proc/mounts
  /dev/sda6 /media/space ext3 rw,nosuid,nodev,relatime,errors=continue,user_xattr,acl,data=ordered 0 0

  We can see the "barrier=1" option is missing by default, which can
  cause severe filesystem corruption in case of power failure (i've been
  hit recently). Quoting mount(1):

  "barrier=0 / barrier=1
  This enables/disables barriers.  barrier=0 disables it, barrier=1 enables it.  Write barriers enforce proper on-disk ordering of journal commits, making volatile disk write caches safe  to  use,  at  some  performance penalty. The ext3 filesystem does not enable write barriers by default. Be sure to enable barriers unless your disks are battery-backed one way or another.  Otherwise you risk filesystem corruption in case of power failure."

  the issue is fixed in later kernels (precise 3.2.0-35 is not
  affected), but lucid users are left to suffer the consequences of this
  horrifying default.

  $ uname -a
  Linux netbook 2.6.32-45-generic #101-Ubuntu SMP Mon Dec 3 15:41:13 UTC 2012 i686 GNU/Linux

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