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Date: Thu, 21 Apr 2011 16:05:52 +0200
From: Matthieu CASTET <matthieu.castet@parrot.com>
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To: "linux-mtd@lists.infradead.org" <linux-mtd@lists.infradead.org>, Brian
	Norris <norris@broadcom.com>
Subject: strange bad block code
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Hi,

while looking at the bad block code, I saw that e0b58d0a introduced a
"chip->badblockbits" for bad block detection in nand_block_bad[1].
That's great because to we can use it to handle bit flip in bad block marker.

But few commit latter c7b28e25cb9 removed "chip->badblockbits = 8;" from common
code.
So now chip->badblockbits = 0.

How such code wan works ?

Adding NAND_SKIP_BBTSCAN in any driver, expose the problem.



[1]
    if (likely(chip->badblockbits == 8))
        res = bad != 0xFF;
    else
        res = hweight8(bad) < chip->badblockbits;