4.15-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 @@ -2199,6 +2199,7 @@ EXPORT_SYMBOL(nand_write_oob_syndrome); 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_to_nand(mtd); struct mtd_ecc_stats stats; @@ -2256,6 +2257,8 @@ 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; @@ -2281,7 +2284,7 @@ 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; } /**