Apparently ECC bytes are not ordered as expected by nand_correct_data() in the ecc_calc buffer which leads to invalid bitflip correction when an ECC error is detected (can be reproduced with 'nandbiterrs -i').
Re-ordering ECC bytes seems to fix the problem.
While at it, get rid of the useless u8 cast.
Fixes: 6c009ab89a21 ("mtd: generic FSMC NAND MTD driver") Cc: stable@vger.kernel.org Signed-off-by: Boris Brezillon boris.brezillon@bootlin.com --- drivers/mtd/nand/raw/fsmc_nand.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/mtd/nand/raw/fsmc_nand.c b/drivers/mtd/nand/raw/fsmc_nand.c index f418236fa020..c79f8e965b38 100644 --- a/drivers/mtd/nand/raw/fsmc_nand.c +++ b/drivers/mtd/nand/raw/fsmc_nand.c @@ -440,9 +440,9 @@ static int fsmc_read_hwecc_ecc1(struct mtd_info *mtd, const uint8_t *data, uint32_t ecc_tmp;
ecc_tmp = readl_relaxed(host->regs_va + ECC1); - ecc[0] = (uint8_t) (ecc_tmp >> 0); - ecc[1] = (uint8_t) (ecc_tmp >> 8); - ecc[2] = (uint8_t) (ecc_tmp >> 16); + ecc[0] = ecc_tmp >> 8; + ecc[1] = ecc_tmp; + ecc[2] = ecc_tmp >> 16;
return 0; }
Hi Boris,
Boris Brezillon boris.brezillon@bootlin.com wrote on Tue, 4 Sep 2018 11:14:38 +0200:
Apparently ECC bytes are not ordered as expected by nand_correct_data() in the ecc_calc buffer which leads to invalid bitflip correction when an ECC error is detected (can be reproduced with 'nandbiterrs -i').
Re-ordering ECC bytes seems to fix the problem.
While at it, get rid of the useless u8 cast.
Fixes: 6c009ab89a21 ("mtd: generic FSMC NAND MTD driver") Cc: stable@vger.kernel.org Signed-off-by: Boris Brezillon boris.brezillon@bootlin.com
drivers/mtd/nand/raw/fsmc_nand.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
Acked-by: Miquel Raynal miquel.raynal@bootlin.com
Thanks, Miquèl
On Tue, Sep 4, 2018 at 11:14 AM Boris Brezillon boris.brezillon@bootlin.com wrote:
Apparently ECC bytes are not ordered as expected by nand_correct_data() in the ecc_calc buffer which leads to invalid bitflip correction when an ECC error is detected (can be reproduced with 'nandbiterrs -i').
Re-ordering ECC bytes seems to fix the problem.
While at it, get rid of the useless u8 cast.
Fixes: 6c009ab89a21 ("mtd: generic FSMC NAND MTD driver") Cc: stable@vger.kernel.org Signed-off-by: Boris Brezillon boris.brezillon@bootlin.com
Acked-by: Linus Walleij linus.walleij@linaro.org
Yours, Linus Walleij
On Tue, 4 Sep 2018 11:14:38 +0200 Boris Brezillon boris.brezillon@bootlin.com wrote:
Apparently ECC bytes are not ordered as expected by nand_correct_data() in the ecc_calc buffer which leads to invalid bitflip correction when an ECC error is detected (can be reproduced with 'nandbiterrs -i').
Re-ordering ECC bytes seems to fix the problem.
While at it, get rid of the useless u8 cast.
Fixes: 6c009ab89a21 ("mtd: generic FSMC NAND MTD driver") Cc: stable@vger.kernel.org Signed-off-by: Boris Brezillon boris.brezillon@bootlin.com
drivers/mtd/nand/raw/fsmc_nand.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/mtd/nand/raw/fsmc_nand.c b/drivers/mtd/nand/raw/fsmc_nand.c index f418236fa020..c79f8e965b38 100644 --- a/drivers/mtd/nand/raw/fsmc_nand.c +++ b/drivers/mtd/nand/raw/fsmc_nand.c @@ -440,9 +440,9 @@ static int fsmc_read_hwecc_ecc1(struct mtd_info *mtd, const uint8_t *data, uint32_t ecc_tmp; ecc_tmp = readl_relaxed(host->regs_va + ECC1);
- ecc[0] = (uint8_t) (ecc_tmp >> 0);
- ecc[1] = (uint8_t) (ecc_tmp >> 8);
- ecc[2] = (uint8_t) (ecc_tmp >> 16);
- ecc[0] = ecc_tmp >> 8;
- ecc[1] = ecc_tmp;
- ecc[2] = ecc_tmp >> 16;
Hm, looks like there's a Kconfig option (CONFIG_MTD_NAND_ECC_SMC) to let nand_ecc_correct() swap those 2 bytes for us, but it's clearly not a good thing to take this decision based on a Kconfig option (does not work if you want the same kernel to be used on various platforms).
I'll come up with a better solution.
linux-stable-mirror@lists.linaro.org
-
Boris Brezillon -
Linus Walleij -
Miquel Raynal