>
> Hi,
>
> How XFS reacts while trying to read from damaged area
> (i.e. bad blocks on hard drive)? One of my disks
> unfortunately got bad sectors and XFS reaction was:
> "Kernel Panic" (as far as i know it's normal reaction
> - the journalling fs idea does _not_ handle with
> damaged block devices) .... What would be the best
> way to got the data (not on the damaged area) back?
>
> - Krzysztof
>
> PS.
> that "panic" is reproducable on particular file...
This discussion just came up internally yesterday, XFS was originally
written on a system where bad block handling was totally below the
filesystem, as it is on almost everything now. The final result
should not be a kernel panic, but for the filesystem to shut itself
down, this is not working yet though.
However, that aside, it rather depends on what XFS had living on the
bad blocks, from the sound of it it appears to be metadata. You say
the panic is related to a particular file - do you need contents of
this file, or the rest of the filesystem, also, is the error related to
looking at the inode (ls does it) or contents (cat does it)?
If the panic was restricted to this file then you could copy off the
rest of the filesystem and avoid this one.
If you want the contents of the file things get harder - we would need
to see the panic and where it is coming from - it may be possible to
modify the kernel a little bit to just ignore the error and carry on,
it depends on what it is.
Steve
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