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: <[email protected]>
Signed-off-by: Abhishek Sahu <[email protected]>
---
drivers/mtd/nand/raw/nand_base.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/mtd/nand/raw/nand_base.c b/drivers/mtd/nand/raw/nand_base.c
index f28c3a5..4a73f73 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];
--
QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc.
is a member of Code Aurora Forum, hosted by The Linux Foundation
Hi Boris,
On Wed, 13 Jun 2018 14:32:36 +0530, Abhishek Sahu
<[email protected]> wrote:
> 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: <[email protected]>
> Signed-off-by: Abhishek Sahu <[email protected]>
> ---
> drivers/mtd/nand/raw/nand_base.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/mtd/nand/raw/nand_base.c b/drivers/mtd/nand/raw/nand_base.c
> index f28c3a5..4a73f73 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];
Reviewed-by: Miquel Raynal <[email protected]>
I suppose this patch is a good candidate to be part of a future
mtd/fixes PR?
Regards,
Miquèl
On Mon, 18 Jun 2018 15:57:57 +0200
Miquel Raynal <[email protected]> wrote:
> Hi Boris,
>
> On Wed, 13 Jun 2018 14:32:36 +0530, Abhishek Sahu
> <[email protected]> wrote:
>
> > 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: <[email protected]>
> > Signed-off-by: Abhishek Sahu <[email protected]>
> > ---
> > drivers/mtd/nand/raw/nand_base.c | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/mtd/nand/raw/nand_base.c b/drivers/mtd/nand/raw/nand_base.c
> > index f28c3a5..4a73f73 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];
>
> Reviewed-by: Miquel Raynal <[email protected]>
Applied.
Thanks,
Boris
>
> I suppose this patch is a good candidate to be part of a future
> mtd/fixes PR?
>
> Regards,
> Miquèl
>
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