bbt and bitflip

[Matthieu CASTET]

Matthieu CASTET a écrit :
> Hi,
> 
> the current bad block table implementation doesn't seem robust against bit flip.
> 
> at boot we call :
> - search_read_bbts which scan for bbt using oob pattern.
> - check_create
> -- read_abs_bbt
> --- read_bbt which ignore ecc bit flip/error
> 
> So if bit flip happen in BBT, we never scrub it.
> And if bit flip accumulate and we can't correct it anymore, the code will parse
> the corrupted data and our bad block info will be wrong (valid block can be
> marked as bad and we lose bad, bad block can be see as valid).
> 
> 
> Also the pattern and version in oob isn't protected by ecc. They can be corrupted.
> 
> Are bbt safe to use ?
> 
> Are there any plan to make the bbt more robust ?
> 
Here a quick and dirty patch to make them more robust.
Any comment are welcomed.


Matthieu
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