Re: [PATCH md ] Better handling of readerrors with raid5.

[Molle Bestefich <molle.bestefich@gmail.com>]

NeilBrown wrote:
> TESTERS WANTED!!  SEE BELOW...
> 
> This patch changes the behaviour of raid5 when it gets a read error.
> Instead of just failing the device, it tried to find out what should
> have been there, and writes it over the bad block.

Jip-hee!  Beautiful!!
Neil, a big, warm and fuzzy Thank You for all the hard work you put into MD!

I do not have a test system, so I've tried to apply the patch to a
smallish (6 disk ata) live system instead.  (Am I sane?)

Some of the disks have probably developed a couple of bad blocks here
and there by now.  I imagine doing a 'dd' from the MD device will read
at least 83% of all sectors (?), so there's a fair chance I'll hit
something if it's there.

Applying the patch doesn't quite work for me:
==============================================
linux-2.6.13.2 # patch --dry-run -p0 < md-rewrite-bad-blocks.patch
patching file ./drivers/md/raid5.c
Hunk #1 succeeded at 339 (offset -10 lines).
Hunk #3 succeeded at 963 (offset -20 lines).
Hunk #4 FAILED at 983.
Hunk #5 succeeded at 1044 (offset -2 lines).
Hunk #6 succeeded at 1274 (offset -32 lines).
1 out of 6 hunks FAILED -- saving rejects to file ./drivers/md/raid5.c.rej
patching file ./include/linux/raid/raid5.h
Hunk #1 succeeded at 153 (offset -1 lines).
==============================================

Hunk #4 succeds if given a fuzz of 3...
Is it safe to use the patch with 2.6.13.2?