The patch below does not apply to the 4.14-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable@xxxxxxxxxxxxxxx>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From e9893e6fa932f42c90c4ac5849fa9aa0f0f00a34 Mon Sep 17 00:00:00 2001 From: Abhishek Sahu <absahu@xxxxxxxxxxxxxx> Date: Wed, 13 Jun 2018 14:32:36 +0530 Subject: [PATCH] mtd: rawnand: fix return value check for bad block status Positive return value from read_oob() is making false BAD blocks. For some of the NAND controllers, OOB bytes will be protected with ECC and read_oob() will return number of bitflips. If there is any bitflip in ECC protected OOB bytes for BAD block status page, then that block is getting treated as BAD. Fixes: c120e75e0e7d ("mtd: nand: use read_oob() instead of cmdfunc() for bad block check") Cc: <stable@xxxxxxxxxxxxxxx> Signed-off-by: Abhishek Sahu <absahu@xxxxxxxxxxxxxx> Reviewed-by: Miquel Raynal <miquel.raynal@xxxxxxxxxxx> Signed-off-by: Boris Brezillon <boris.brezillon@xxxxxxxxxxx> diff --git a/drivers/mtd/nand/raw/nand_base.c b/drivers/mtd/nand/raw/nand_base.c index 10c4f9919850..b01d15ec4c56 100644 --- a/drivers/mtd/nand/raw/nand_base.c +++ b/drivers/mtd/nand/raw/nand_base.c @@ -440,7 +440,7 @@ static int nand_block_bad(struct mtd_info *mtd, loff_t ofs) for (; page < page_end; page++) { res = chip->ecc.read_oob(mtd, chip, page); - if (res) + if (res < 0) return res; bad = chip->oob_poi[chip->badblockpos];