Recovering data from bad hard disk sectors ? (WAS: Feisty: recent updates causing freezes ??)

[Vincent Trouilliez]

> Magic SysRq Key is your friend.
> http://www.linuxhowtos.org/Tips%20and%20Tricks/sysrq.htm

Wow, that's quite interesting !! :-)
Thanks for sharing...

I think I found the source of my problem. It was probably a dodgy hard
drive causing the crashes. Today it crashed one more time, but this
time it got worse: Ubuntu could start, but the kernel failed to mount
my /home partition, filling the screen with Buffer I/O errors !!! :-O

The other partitions on the disk appear to be healthy (enough anyway)
for Ubuntu to start, though obviously I can't log into a now
non-existing /home...

This is the typical kernel error sequence/pattern that gets repeated
over and over again during the boot process, everytime it wants to
access my /home partition (/dev/hda7) for one reason or another:

---------
hda: dma_intr: status=0x51 { DriveReady SeekComplete Error } 
hda: dma_intr: error=0x40 { UncorrectableError },
LBAsect=37110239,high=2, low=3555807, sector=37110225
ide: failed opcode was: unknown 
end_request: I/O error, dev hda, sector 37110225 Buffer I/O error on
device hda7, logical block 3 
---------

If I understand, the drive has developped bad sectors inside my home
partition, bad luck.... :-/ Is there any recovery tool that could
perhaps get some of my data back, from the remaining, healthy sectors
of the partition ? That would be great... I have lost a lot, the last
15 years of my life, so if I can recover some bits and bobs, no matter
how little, I would be glad ! Yes yes, I will now think seriously of
setting up a back up system of some sort, and run it regularly... I
fully understand that I just got what I deserved... I should not have
trusted a hard drive, eventhough it was only a few months old...
Still, if the problem is bad sectors as it seems... isn't a file
system, supposed to mark such sectors so as not to put data on it ?

Thanks in advance for any help...

-- 
Vince