Erasing NAND bad blocks?

[Steven Hein <ssh@sgi.com>]

(Yes, I do know that erasing NAND flash blocks that are marked bad
is a VERY BAD IDEA.....I'm asking the question regarding a
specific HW/SW debug situation.......)

In the course of bringing up new hardware with NAND flash attached
I have had occasions where a software bug will cause a NAND-based
filesystem (such as YAFFS) to mark *all* of the blocks in a filesystem
as bad.  In the past, I have hacked the nand_erase() function to
allow erasing of bad blocks, then wrote a custom app to scan the OOB
data, doing a MEM_ERASE for blocks that had been marked bad by the FS.
Just wondering.....has anyone else
run into this situation, and is there a more graceful way of doing
this (i.e. without hacking the MTD NAND driver)?

Thanks!
Steve

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Steve Hein (ssh@sgi.com)              Engineering Diagnostics/Software
Silicon Graphics, Inc.                          
1168 Industrial Blvd.                 Phone: (715) 726-8410
Chippewa Falls, WI 54729              Fax:   (715) 726-6715
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