Re: [PATCH v4 1/3] iio:pressure:ms5611: fix oops when probing regulator
From: Jonathan Cameron <hidden>
Date: 2016-03-05 14:36:08
Also in:
linux-iio
On 01/03/16 10:31, Gregor Boirie wrote:
When not compiled-in, regulator layer will return a NULL pointer when trying to get a reference to any regulator using devm_regulator_get(). As IS_ERR() does not consider this an error, the ms5611 probing operation will try to enable a NULL regulator, which will invariably cause a kernel crash. This patch fixes this situation by using devm_regulator_get_optional() instead of devm_regulator_get(). Signed-off-by: Gregor Boirie <gregor.boirie-ITF29qwbsa/QT0dZR+AlfA@public.gmane.org>
Ideally include a fixes tag with a patch like this... It makes it easy for those maintaining stable trees to figure out whether it is 'supposed' to apply to their trees or not.
quoted hunk
--- drivers/iio/pressure/ms5611_core.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-)diff --git a/drivers/iio/pressure/ms5611_core.c b/drivers/iio/pressure/ms5611_core.c index 992ad8d..a9c4d49 100644 --- a/drivers/iio/pressure/ms5611_core.c +++ b/drivers/iio/pressure/ms5611_core.c@@ -291,8 +291,8 @@ static const struct iio_info ms5611_info = { static int ms5611_init(struct iio_dev *indio_dev) { int ret; - struct regulator *vdd = devm_regulator_get(indio_dev->dev.parent, - "vdd"); + struct regulator *vdd = + devm_regulator_get_optional(indio_dev->dev.parent, "vdd");
Shouldn't have a white space change like this in here. This doesn't want to get applied in a hurry unlike the below. It'll probably be a post merge window fix now...
quoted hunk
/* Enable attached regulator if any. */ if (!IS_ERR(vdd)) {@@ -302,6 +302,10 @@ static int ms5611_init(struct iio_dev *indio_dev) "failed to enable Vdd supply: %d\n", ret); return ret; } + } else { + ret = PTR_ERR(vdd); + if (ret != -ENODEV) + return ret; } ret = ms5611_reset(indio_dev);