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Subject: Re: Cannot erase nand flash
From: Thomas Gleixner <tglx@linutronix.de>
To: Steve Finney <saf76@earthlink.net>
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Date: Mon, 26 Jun 2006 19:19:20 +0200
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On Mon, 2006-06-26 at 10:02 -0700, Steve Finney wrote:
> >Date: Mon, 26 Jun 2006 10:52:43 +0200
> >From: peter.hosten@rwth-aachen.de
> 
> > Unfortunately the mtd-util
> >(flash_eraseall, mtd_debug) is not able to erase the NAND-Flash. I get the
> >error  "./flash_eraseall: /dev/mtd3: MTD Erase failure: Input/output error"
> >(see below)
> 
> >I also dumped the NAND Flash ( see below); may it be possible that it does
> >not work because of the OBB data ( OOB Data: 00 00 00 00 00 00 00 00 00 00
> >00 00 00 00 00 00) ?
> 
> I have seen that error with some versions of mtd-utils when the partition contains a
> bad block, and your dumped OOB would be interpreted as a bad block
> (no 0xFF in byte 5). But, in fact, the flash may have been successfully erased, and Linux
> works reasonably well with bad blocks, so you may be able to just ignore
> the "error".

Err, when oob data are all set to 0, there is something wrong.

	tglx