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From: Thomas Gleixner <tglx@linutronix.de>
To: "David A. Marlin" <dmarlin@redhat.com>
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Date: Thu, 13 Jan 2005 18:48:03 +0100
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Subject: Re: NAND fail testing
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On Thu, 2005-01-13 at 16:55, David A. Marlin wrote:
> Is there a simple way (using existing drivers and utilities) to "wear 
> out" one byte on a NAND type chip by repeatedly rewriting a single byte 
> (single address)?
> 
> I want to cause a single byte failure on a chip in order to perform 
> tests on erase and write error processing, but I only see how to write a 
> 'page' of data, not a single address.
> 

We have blocked the access to short writes. You can do the following:

Erase a block from userspace with flash_erase
Write a page of all 0xff except one byte to the first page using
nandwrite

Repeat until you get an error

tglx