| Message ID | 1480065209-4179-1-git-send-email-boris.brezillon@free-electrons.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 11/25/2016 10:13 AM, Boris Brezillon wrote: > Commit a894cf6c5a82 ("mtd: nand: mxc: switch to mtd_ooblayout_ops") > introduced a bug in the OOB layout description. Even if the driver claims > that 3 ECC bytes are reserved to protect 512 bytes of data, it's actually > 5 ECC bytes to protect 512+6 bytes of data (some OOB bytes are also > protected using extra ECC bytes). > > Fix the mxc_v1_ooblayout_{free,ecc}() functions to reflect this behavior. > > Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> > Fixes: a894cf6c5a82 ("mtd: nand: mxc: switch to mtd_ooblayout_ops") > Cc: <stable@vger.kernel.org> > --- > drivers/mtd/nand/mxc_nand.c | 5 ++--- > 1 file changed, 2 insertions(+), 3 deletions(-) > > diff --git a/drivers/mtd/nand/mxc_nand.c b/drivers/mtd/nand/mxc_nand.c > index 61ca020c5272..c19ec4f0983e 100644 > --- a/drivers/mtd/nand/mxc_nand.c > +++ b/drivers/mtd/nand/mxc_nand.c > @@ -886,7 +886,7 @@ static int mxc_v1_ooblayout_ecc(struct mtd_info *mtd, int section, > return -ERANGE; > > oobregion->offset = (section * 16) + 6; > - oobregion->length = nand_chip->ecc.bytes; > + oobregion->length = 5; Use a macro instead of hard-coding a value please :) > return 0; > } > @@ -908,8 +908,7 @@ static int mxc_v1_ooblayout_free(struct mtd_info *mtd, int section, > oobregion->length = 4; > } > } else { > - oobregion->offset = ((section - 1) * 16) + > - nand_chip->ecc.bytes + 6; > + oobregion->offset = ((section - 1) * 16) + 5 + 6; DTTO here, the math here is cryptic enough. > if (section < nand_chip->ecc.steps) > oobregion->length = (section * 16) + 6 - > oobregion->offset; >
On Fri, 25 Nov 2016 10:58:26 +0100 Marek Vasut <marek.vasut@gmail.com> wrote: > On 11/25/2016 10:13 AM, Boris Brezillon wrote: > > Commit a894cf6c5a82 ("mtd: nand: mxc: switch to mtd_ooblayout_ops") > > introduced a bug in the OOB layout description. Even if the driver claims > > that 3 ECC bytes are reserved to protect 512 bytes of data, it's actually > > 5 ECC bytes to protect 512+6 bytes of data (some OOB bytes are also > > protected using extra ECC bytes). > > > > Fix the mxc_v1_ooblayout_{free,ecc}() functions to reflect this behavior. > > > > Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> > > Fixes: a894cf6c5a82 ("mtd: nand: mxc: switch to mtd_ooblayout_ops") > > Cc: <stable@vger.kernel.org> > > --- > > drivers/mtd/nand/mxc_nand.c | 5 ++--- > > 1 file changed, 2 insertions(+), 3 deletions(-) > > > > diff --git a/drivers/mtd/nand/mxc_nand.c b/drivers/mtd/nand/mxc_nand.c > > index 61ca020c5272..c19ec4f0983e 100644 > > --- a/drivers/mtd/nand/mxc_nand.c > > +++ b/drivers/mtd/nand/mxc_nand.c > > @@ -886,7 +886,7 @@ static int mxc_v1_ooblayout_ecc(struct mtd_info *mtd, int section, > > return -ERANGE; > > > > oobregion->offset = (section * 16) + 6; > > - oobregion->length = nand_chip->ecc.bytes; > > + oobregion->length = 5; > > Use a macro instead of hard-coding a value please :) Ideally, we should change ->eccbytes value in the imx27_nand_devtype_data and imx21_nand_devtype_data definitions, but I fear it could break other things. I'll define a macro. > > > return 0; > > } > > @@ -908,8 +908,7 @@ static int mxc_v1_ooblayout_free(struct mtd_info *mtd, int section, > > oobregion->length = 4; > > } > > } else { > > - oobregion->offset = ((section - 1) * 16) + > > - nand_chip->ecc.bytes + 6; > > + oobregion->offset = ((section - 1) * 16) + 5 + 6; > > DTTO here, the math here is cryptic enough. > > > if (section < nand_chip->ecc.steps) > > oobregion->length = (section * 16) + 6 - > > oobregion->offset; > > > >
On 11/25/2016 11:27 AM, Boris Brezillon wrote: > On Fri, 25 Nov 2016 10:58:26 +0100 > Marek Vasut <marek.vasut@gmail.com> wrote: > >> On 11/25/2016 10:13 AM, Boris Brezillon wrote: >>> Commit a894cf6c5a82 ("mtd: nand: mxc: switch to mtd_ooblayout_ops") >>> introduced a bug in the OOB layout description. Even if the driver claims >>> that 3 ECC bytes are reserved to protect 512 bytes of data, it's actually >>> 5 ECC bytes to protect 512+6 bytes of data (some OOB bytes are also >>> protected using extra ECC bytes). >>> >>> Fix the mxc_v1_ooblayout_{free,ecc}() functions to reflect this behavior. >>> >>> Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> >>> Fixes: a894cf6c5a82 ("mtd: nand: mxc: switch to mtd_ooblayout_ops") >>> Cc: <stable@vger.kernel.org> >>> --- >>> drivers/mtd/nand/mxc_nand.c | 5 ++--- >>> 1 file changed, 2 insertions(+), 3 deletions(-) >>> >>> diff --git a/drivers/mtd/nand/mxc_nand.c b/drivers/mtd/nand/mxc_nand.c >>> index 61ca020c5272..c19ec4f0983e 100644 >>> --- a/drivers/mtd/nand/mxc_nand.c >>> +++ b/drivers/mtd/nand/mxc_nand.c >>> @@ -886,7 +886,7 @@ static int mxc_v1_ooblayout_ecc(struct mtd_info *mtd, int section, >>> return -ERANGE; >>> >>> oobregion->offset = (section * 16) + 6; >>> - oobregion->length = nand_chip->ecc.bytes; >>> + oobregion->length = 5; >> >> Use a macro instead of hard-coding a value please :) > > Ideally, we should change ->eccbytes value in the > imx27_nand_devtype_data and imx21_nand_devtype_data definitions, but I > fear it could break other things. I was wondering about that too :) Break what things ? > I'll define a macro. Thanks! >> >>> return 0; >>> } >>> @@ -908,8 +908,7 @@ static int mxc_v1_ooblayout_free(struct mtd_info *mtd, int section, >>> oobregion->length = 4; >>> } >>> } else { >>> - oobregion->offset = ((section - 1) * 16) + >>> - nand_chip->ecc.bytes + 6; >>> + oobregion->offset = ((section - 1) * 16) + 5 + 6; >> >> DTTO here, the math here is cryptic enough. >> >>> if (section < nand_chip->ecc.steps) >>> oobregion->length = (section * 16) + 6 - >>> oobregion->offset; >>> >> >> >
diff --git a/drivers/mtd/nand/mxc_nand.c b/drivers/mtd/nand/mxc_nand.c index 61ca020c5272..c19ec4f0983e 100644 --- a/drivers/mtd/nand/mxc_nand.c +++ b/drivers/mtd/nand/mxc_nand.c @@ -886,7 +886,7 @@ static int mxc_v1_ooblayout_ecc(struct mtd_info *mtd, int section, return -ERANGE; oobregion->offset = (section * 16) + 6; - oobregion->length = nand_chip->ecc.bytes; + oobregion->length = 5; return 0; } @@ -908,8 +908,7 @@ static int mxc_v1_ooblayout_free(struct mtd_info *mtd, int section, oobregion->length = 4; } } else { - oobregion->offset = ((section - 1) * 16) + - nand_chip->ecc.bytes + 6; + oobregion->offset = ((section - 1) * 16) + 5 + 6; if (section < nand_chip->ecc.steps) oobregion->length = (section * 16) + 6 - oobregion->offset;
Commit a894cf6c5a82 ("mtd: nand: mxc: switch to mtd_ooblayout_ops") introduced a bug in the OOB layout description. Even if the driver claims that 3 ECC bytes are reserved to protect 512 bytes of data, it's actually 5 ECC bytes to protect 512+6 bytes of data (some OOB bytes are also protected using extra ECC bytes). Fix the mxc_v1_ooblayout_{free,ecc}() functions to reflect this behavior. Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> Fixes: a894cf6c5a82 ("mtd: nand: mxc: switch to mtd_ooblayout_ops") Cc: <stable@vger.kernel.org> --- drivers/mtd/nand/mxc_nand.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-)