4.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Miquel Raynal <miquel.raynal@xxxxxxxxxxxxxxxxxx>
commit 87e89ce8d0d14f573c068c61bec2117751fb5103 upstream.
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()")
Signed-off-by: Miquel Raynal <miquel.raynal@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Boris Brezillon <boris.brezillon@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/mtd/nand/nand_base.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
--- a/drivers/mtd/nand/nand_base.c
+++ b/drivers/mtd/nand/nand_base.c
@@ -2023,6 +2023,7 @@ static int nand_write_oob_syndrome(struc
static int nand_do_read_oob(struct mtd_info *mtd, loff_t from,
struct mtd_oob_ops *ops)
{
+ unsigned int max_bitflips = 0;
int page, realpage, chipnr;
struct nand_chip *chip = mtd->priv;
struct mtd_ecc_stats stats;
@@ -2083,6 +2084,8 @@ static int nand_do_read_oob(struct mtd_i
nand_wait_ready(mtd);
}
+ max_bitflips = max_t(unsigned int, max_bitflips, ret);
+
readlen -= len;
if (!readlen)
break;
@@ -2108,7 +2111,7 @@ static int nand_do_read_oob(struct mtd_i
if (mtd->ecc_stats.failed - stats.failed)
return -EBADMSG;
- return mtd->ecc_stats.corrected - stats.corrected ? -EUCLEAN : 0;
+ return max_bitflips;
}
/**