Hi Paolo, Hi Jonathan, On Sat, Jun 3, 2017 at 10:52 AM, Jonathan Cameron <jic23@xxxxxxxxxx> wrote: > On Sun, 28 May 2017 23:17:57 +0200 > Martin Blumenstingl <martin.blumenstingl@xxxxxxxxxxxxxx> wrote: > >> Hi Paolo, Hi Jonathan, >> >> On Sun, May 28, 2017 at 4:43 PM, Jonathan Cameron <jic23@xxxxxxxxxx> wrote: >> > On Sun, 28 May 2017 13:24:38 +0200 >> > Paolo Cretaro <paolocretaro@xxxxxxxxx> wrote: >> > >> >> Fix sparse warning: Using plain integer as NULL pointer >> >> >> >> Signed-off-by: Paolo Cretaro <paolocretaro@xxxxxxxxx> >> > This looks fine to me, but ideally you should always try to include >> > the driver author - particularly in the case of patches to a recent >> > driver such as this one. >> > >> > To that end I've cc'd Martin. >> thanks for spotting this (and providing a patch to fix it) >> this looks good to me, so: >> Acked-by: Martin Blumenstingl <martin.blumenstingl@xxxxxxxxxxxxxx> >> >> if you can wait until next weekend then I can also test this on real hardware. > I've applied it to the togreg branch of iio.git but as that always goes out > as testing for at least a few days first (which I will happily rebase) give > me a shout if anything goes wrong! I have tested this on actual hardware and it seems that there's a bug in the meson-saradc driver (before and after this patch): if there are still "old" values in the FIFO then the driver currently crashes because regmap_read (regmap_mmio_read in case of the meson-saradc driver to be precise) de-references the "value" pointer (the parameter which we're trying to clean up here) -> this leads to a NULL de-reference. this happens regardless of whether we are passing "0" or "NULL" I posted a patch which fixes the crash - and as a bonus this should also fix the sparse warning reported by Paolo: http://lists.infradead.org/pipermail/linux-amlogic/2017-June/003863.html > Jonathan >> >> > Jonathan >> >> --- >> >> drivers/iio/adc/meson_saradc.c | 2 +- >> >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> >> >> diff --git a/drivers/iio/adc/meson_saradc.c b/drivers/iio/adc/meson_saradc.c >> >> index 81cd39a57fe3..fb3f67a9ae1f 100644 >> >> --- a/drivers/iio/adc/meson_saradc.c >> >> +++ b/drivers/iio/adc/meson_saradc.c >> >> @@ -481,7 +481,7 @@ static void meson_sar_adc_clear_fifo(struct iio_dev *indio_dev) >> >> if (!meson_sar_adc_get_fifo_count(indio_dev)) >> >> break; >> >> >> >> - regmap_read(priv->regmap, MESON_SAR_ADC_FIFO_RD, 0); >> >> + regmap_read(priv->regmap, MESON_SAR_ADC_FIFO_RD, NULL); >> >> } >> >> } >> >> >> > >> >> Regards, >> Martin > -- 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
