On Thu, 11 Jan 2018 22:42:02 +0100
Miquel Raynal <miquel.raynal@xxxxxxxxxxxxxxxxxx> wrote:
> Starting from commit 041e4575f034 ("mtd: nand: handle ECC errors in
> OOB"), nand_do_read_oob() (from the NAND core) did return 0 or a
> negative error, and the MTD layer expected it.
>
> However, the trend for the NAND layer is now to return an error or a
> positive number of bitflips. Deciding which status to return to the user
> belongs to the MTD layer.
>
> Commit e47f68587b82 ("mtd: check for max_bitflips in mtd_read_oob()")
> brought this logic to the mtd_read_oob() function while the return value
> coming from nand_do_read_oob() (called by the ->_read_oob() hook) was
> left unchanged.
>
> Fixes: e47f68587b82 ("mtd: check for max_bitflips in mtd_read_oob()")
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Miquel Raynal <miquel.raynal@xxxxxxxxxxxxxxxxxx>
> ---
>
> Changes since v1:
> - s/->ecc.read_oob() hook/->_read_oob() hook/ in the commit message
> - Fixed the compilation issue
>
> drivers/mtd/nand/nand_base.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
> index 469220065b8b..440d9f5d5b17 100644
> --- a/drivers/mtd/nand/nand_base.c
> +++ b/drivers/mtd/nand/nand_base.c
> @@ -3876,7 +3876,7 @@ static int nand_do_read_oob(struct mtd_info *mtd, loff_t from,
> if (mtd->ecc_stats.failed - stats.failed)
> return -EBADMSG;
>
> - return mtd->ecc_stats.corrected - stats.corrected ? -EUCLEAN : 0;
> + return ret;
This is wrong, you're only returning the max number of bitflips of the
last OOB read.
> }
>
> /**