On 04/02/2017 11:26 AM, Jonathan Cameron wrote: > On 25/03/17 18:03, Jonathan Cameron wrote: >> On 24/03/17 12:41, Nikolaus Schulz wrote: >>> Fix formatting of negative values of type IIO_VAL_FRACTIONAL_LOG2 by >>> switching from do_div(), which can't handle negative numbers, to >>> div_s64_rem(). Also use shift_right for shifting, which is safe with >>> negative values. >>> >>> Signed-off-by: Nikolaus Schulz <nikolaus.schulz@xxxxxxxxxxxxxxxxx> >>> Cc: stable@xxxxxxxxxxxxxxx >> Looks sane to me, but I'd like to give others time to comment on this >> just in case there is some odd condition neither of us has thought of! >> >> Give me a poke if we get nothing else for a few weeks. > Lars, I think this might have been your magic in the first place. > > Could you sanity check this one please. It's in the category of very > risky of both Nikolaus and I have missed something! It's the same as this: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/drivers/iio/industrialio-core.c?id=171c0091837c81ed5c949fec6966bb5afff2d1cf Should be OK. Reviewed-by: Lars-Peter Clausen <lars@xxxxxxxxxx> > > Thanks, > > Jonathan >> >> Jonathan >>> --- >>> drivers/iio/industrialio-core.c | 7 +++---- >>> 1 file changed, 3 insertions(+), 4 deletions(-) >>> >>> diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c >>> index d18ded4..3ff91e0 100644 >>> --- a/drivers/iio/industrialio-core.c >>> +++ b/drivers/iio/industrialio-core.c >>> @@ -610,10 +610,9 @@ static ssize_t __iio_format_value(char *buf, size_t len, unsigned int type, >>> tmp0 = (int)div_s64_rem(tmp, 1000000000, &tmp1); >>> return snprintf(buf, len, "%d.%09u", tmp0, abs(tmp1)); >>> case IIO_VAL_FRACTIONAL_LOG2: >>> - tmp = (s64)vals[0] * 1000000000LL >> vals[1]; >>> - tmp1 = do_div(tmp, 1000000000LL); >>> - tmp0 = tmp; >>> - return snprintf(buf, len, "%d.%09u", tmp0, tmp1); >>> + tmp = shift_right((s64)vals[0] * 1000000000LL, vals[1]); >>> + tmp0 = (int)div_s64_rem(tmp, 1000000000LL, &tmp1); >>> + return snprintf(buf, len, "%d.%09u", tmp0, abs(tmp1)); >>> case IIO_VAL_INT_MULTIPLE: >>> { >>> int i; >>> >> >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-iio" in >> the body of a message to majordomo@xxxxxxxxxxxxxxx >> More majordomo info at http://vger.kernel.org/majordomo-info.html >> > > -- > To unsubscribe from this list: send the line "unsubscribe linux-iio" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html >