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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 19:15:57 +0100
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Subject: Re: NAND fail testing
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On Thu, 2005-01-13 at 18:56, David A. Marlin wrote:
> Thomas Gleixner wrote:
> 
> > 
> > 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
> 
> Would this not still 'write' all bytes in the page (even though they are 
> 0xff and unchanged), causing them to also wear and possibly fail?

Since the write is only from 1 -> 0 the page write command always
"writes" all bytes regardless of the number of bytes you have supplied
before. 

tglx