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From: Matthieu CASTET <matthieu.castet@parrot.com>
To: "linux-mtd@lists.infradead.org" <linux-mtd@lists.infradead.org>
Subject: bbt and bitflip
Date: Thu, 21 Apr 2011 15:40:52 +0200	[thread overview]
Message-ID: <4DB033E4.6030105@parrot.com> (raw)

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 ?

             reply	other threads:[~2011-04-21 13:41 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-04-21 13:40 Matthieu CASTET [this message]
2011-04-21 17:17 ` bbt and bitflip Matthieu CASTET
2011-04-22  8:14   ` Artem Bityutskiy
2011-04-22  8:15   ` Artem Bityutskiy
2011-06-23 16:36     ` Brian Norris
2011-06-24 19:55       ` Artem Bityutskiy
2011-06-24 20:36         ` Matthew L. Creech
2011-04-22  8:08 ` Artem Bityutskiy

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