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From: Iwo Mergler <iwo@call-direct.com.au>
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To: Matthieu CASTET <matthieu.castet@parrot.com>
Subject: Re: [BUG] JFFS2 power loss recovery issues on NAND
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Cc: dwmw2@infradead.org, joern@logfs.org, linux-mtd@lists.infradead.org,
	Alexey Korolev <akorolev@infradead.org>
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Matthieu CASTET wrote:
> Iwo Mergler wrote:
>> Alexey Korolev wrote:
>>>   
>> Alexey,
>>
>> I know of at least one hardware ECC implementation which can flag
>> errors within the ECC bytes separately. In other words, not all 
>> implementations
>> will detect/correct bit errors in the case of a ECC write error.
>>
>> About how to fix it - what about making the reading without ECC the 
>> default
>> and only re-reading with ECC if JFFS2 finds an invalid checksum?
>>
> But what happen if a but flip happen ?
> If we do this, ecc won't correct it, the error can happen everywhere 
> not only in checksum, for example wrong nodetype.
Forgive my ignorance - does that mean that not everything in JFFS2 is 
CRC protected?

If that is the case, forget my suggestion. I don't know JFFS2 that 
intimately. :-)

Kind regards,

Iwo