Re: Disk errors and Reiserfs

[Brian]

On Sunday 16 September 2001 08:40 pm, Alan Cox wrote:
> > My issue, though, is Linux did not handle it well.  Userspace actually
> > has an 'EIO' error code for this situation but, instead, any program
> > touching the mounted partition hung in a D state.
>
> Thats a reiserfs property and one you'll find in pretty much any other
> fs.

Is that the best approach?  Userspace doesn't always handle EIO well, but 
it can't do much worse than a permanent deadlock.

> > Is it possible for the kernel to handle this with enough grace that
> > you can kill the processes and unmount the partition?  (Thus allowing
> > the box to continue in a hobbled, but function manner.)  Failing that,
> > is it possible for the kernel to handle it well enough for 'shutdown'
> > to cleanly shutdown the box?
>
> Killing the process isnt neccessary, its been halted in its tracks. As
> to a clean shutdown - no chance. You've just hit a disk failure, the on
> disk state is not precisely known, writes have been lost. Nothing is
> going to make a clean shutdown possible under such circumstances.

Let me rephrase: cleanish.  At least enough to let 'shutdown' actually 
shutdown and surviving filesystems to unmount cleanly.  I guess this would 
require all file ops to that filesystem to return EIO and umount would 
drop the filesystem as-is.

	-- Brian