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 for linux-mtd@lists.infradead.org; Sun, 19 Mar 2017 20:34:49 +0000
Subject: Re: One bit flip in erased page causes uncorrectable error using
 (LS1020A) HW ECC
To: Kees Trommel <ctrommel@aimvalley.nl>,
 Richard Weinberger <richard.weinberger@gmail.com>
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Cc: Linux MTD <linux-mtd@lists.infradead.org>,
 Norbert van Bolhuis <nvbolhuis@aimvalley.nl>
From: Richard Weinberger <richard@nod.at>
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Kees,

Am 14.03.2017 um 16:56 schrieb Kees Trommel:
> Richard,
> 
>> So, I fear your driver needs a better way to work around these bit flips
> 
> That was I afraid of, thanks for you answer.
> 
>> What exactly does UBI report?
> 
> fsl,ifc-nand 7e800000.flash: NAND Flash ECC Uncorrectable Error
> ubi0 warning: ubi_io_read: error -74 (ECC error) while reading 4096 bytes from PEB 500:4096, read only 4096 bytes, retry
> fsl,ifc-nand 7e800000.flash: NAND Flash ECC Uncorrectable Error
> ubi0 warning: ubi_io_read: error -74 (ECC error) while reading 4096 bytes from PEB 500:4096, read only 4096 bytes, retry
> fsl,ifc-nand 7e800000.flash: NAND Flash ECC Uncorrectable Error
> ubi0 warning: ubi_io_read: error -74 (ECC error) while reading 4096 bytes from PEB 500:4096, read only 4096 bytes, retry
> fsl,ifc-nand 7e800000.flash: NAND Flash ECC Uncorrectable Error
> ubi0 error: ubi_io_read: error -74 (ECC error) while reading 4096 bytes from PEB 500:4096, read 4096 bytes

Did you verify whether the data on PEB 500 are really 0xff bytes with bit-flips?

Thanks,
//richard