[Bug 28622] Warning should be displayed when a filesystem is remounted read-only.

[Scott Bronson]

Public bug reported:
https://launchpad.net/malone/bugs/28622

Affects: hal (Ubuntu)
       Severity: Normal
       Priority: (none set)
         Status: Unconfirmed

Description:
When the kernel notices massive data corruption or a hardware failure,
it remounts the affected partitions read-only.  However, the user is
never notified.  When random stuff suddenly starts breaking or acting
really weird, the user will likeliy reboot the computer and miss an
important opportunity to back up valuable files.

Instead, when the kernel remounts a partition r/o a dialog box should
pop up saying, "Warning!  Disk failure on /home.  Please limit your
activity to a minimum and copy all valuable files to a more reliable
location."

In this log, /dev/hda6, the /home partition, fails:

hermanr__ [6617016.214000] hda: dma_intr: status=0x51 { DriveReady SeekComplete Error }
hermanr__ [6617016.214000] hda: dma_intr: error=0x40 { UncorrectableError }, LBAsect=12640272, high=0, low=12640272, sector=12640271
hermanr__ [6617016.214000] ide: failed opcode was: unknown
hermanr__ [6617016.214000] end_request: I/O error, dev hda, sector 12640271
hermanr__ [6617016.214000] journal_bmap: journal block not found at offset 5132 on hda6
hermanr__ [6617016.214000] Aborting journal on device hda6.
hermanr__ [6617016.366000] ext3_abort called.
hermanr__ [6617016.366000] EXT3-fs error (device hda6): ext3_journal_start_sb: Detected aborted journal
hermanr__ [6617016.366000] Remounting filesystem read-only

There are probably other kernel failures that would warrant a warning
dialog too but, due to the probable data loss, this one seems the most
important.

filed against the hal package because I don't know of a better package
to handle this.  Filed on behalf of Herman Robak after a discussion over
IRC.