[PATCH v1 0/2] iio: adc: Check for error from devm_mutex_init()

[PATCH v1 0/2] iio: adc: Check for error from devm_mutex_init()

[Andy Shevchenko]

Ignoring error checking from devm calls is a bad practice in general.
While not critical today, it may become a problem tomorrow.
Fix this for devm_mutex_init().

Andy Shevchenko (2):
  iio: adc: ad4000: Check for error code from devm_mutex_init() call
  iio: adc: pac1921: Check for error code from devm_mutex_init() call

 drivers/iio/adc/ad4000.c  | 4 +++-
 drivers/iio/adc/pac1921.c | 4 +++-
 2 files changed, 6 insertions(+), 2 deletions(-)

-- 
2.43.0.rc1.1336.g36b5255a03ac

[PATCH v1 1/2] iio: adc: ad4000: Check for error code from devm_mutex_init() call

[Andy Shevchenko]

Even if it's not critical, the avoidance of checking the error code
from devm_mutex_init() call today diminishes the point of using devm
variant of it. Tomorrow it may even leak something. Add the missed
check.

Fixes: 938fd562b974 ("iio: adc: Add support for AD4000")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 drivers/iio/adc/ad4000.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/iio/adc/ad4000.c b/drivers/iio/adc/ad4000.c
index 6ea491245084..b4a23c97ee52 100644
--- a/drivers/iio/adc/ad4000.c
+++ b/drivers/iio/adc/ad4000.c
@@ -637,7 +637,9 @@ static int ad4000_probe(struct spi_device *spi)
 	indio_dev->name = chip->dev_name;
 	indio_dev->num_channels = 1;
 
-	devm_mutex_init(dev, &st->lock);
+	ret = devm_mutex_init(dev, &st->lock);
+	if (ret)
+		return ret;
 
 	st->gain_milli = 1000;
 	if (chip->has_hardware_gain) {
-- 
2.43.0.rc1.1336.g36b5255a03ac

[PATCH v1 2/2] iio: adc: pac1921: Check for error code from devm_mutex_init() call

[Andy Shevchenko]

Even if it's not critical, the avoidance of checking the error code
from devm_mutex_init() call today diminishes the point of using devm
variant of it. Tomorrow it may even leak something. Add the missed
check.

Fixes: 371f778b83cd ("iio: adc: add support for pac1921")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 drivers/iio/adc/pac1921.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/iio/adc/pac1921.c b/drivers/iio/adc/pac1921.c
index f6f8f9122a78..385e86ecc441 100644
--- a/drivers/iio/adc/pac1921.c
+++ b/drivers/iio/adc/pac1921.c
@@ -1132,7 +1132,9 @@ static int pac1921_probe(struct i2c_client *client)
 		return dev_err_probe(dev, PTR_ERR(priv->regmap),
 				     "Cannot initialize register map\n");
 
-	devm_mutex_init(dev, &priv->lock);
+	ret = devm_mutex_init(dev, &priv->lock);
+	if (ret)
+		return ret;
 
 	priv->dv_gain = PAC1921_DEFAULT_DV_GAIN;
 	priv->di_gain = PAC1921_DEFAULT_DI_GAIN;
-- 
2.43.0.rc1.1336.g36b5255a03ac

Re: [PATCH v1 2/2] iio: adc: pac1921: Check for error code from devm_mutex_init() call

[Matteo Martelli]

Quoting Andy Shevchenko (2024-10-30 17:19:19)
> Even if it's not critical, the avoidance of checking the error code
> from devm_mutex_init() call today diminishes the point of using devm
> variant of it. Tomorrow it may even leak something. Add the missed
> check.
> 
> Fixes: 371f778b83cd ("iio: adc: add support for pac1921")
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> ---
>  drivers/iio/adc/pac1921.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/iio/adc/pac1921.c b/drivers/iio/adc/pac1921.c
> index f6f8f9122a78..385e86ecc441 100644
> --- a/drivers/iio/adc/pac1921.c
> +++ b/drivers/iio/adc/pac1921.c
> @@ -1132,7 +1132,9 @@ static int pac1921_probe(struct i2c_client *client)
>                 return dev_err_probe(dev, PTR_ERR(priv->regmap),
>                                      "Cannot initialize register map\n");
>  
> -       devm_mutex_init(dev, &priv->lock);
> +       ret = devm_mutex_init(dev, &priv->lock);
> +       if (ret)
> +               return ret;
>  
>         priv->dv_gain = PAC1921_DEFAULT_DV_GAIN;
>         priv->di_gain = PAC1921_DEFAULT_DI_GAIN;
> -- 
> 2.43.0.rc1.1336.g36b5255a03ac
> 

Totally agree, thanks!

Acked-by: Matteo Martelli <matteomartelli3@gmail.com>

Best regards,
Matteo Martelli

Re: [PATCH v1 0/2] iio: adc: Check for error from devm_mutex_init()

[Jonathan Cameron]

On Wed, 30 Oct 2024 18:19:17 +0200
Andy Shevchenko <andriy.shevchenko@linux.intel.com> wrote:

> Ignoring error checking from devm calls is a bad practice in general.
> While not critical today, it may become a problem tomorrow.
> Fix this for devm_mutex_init().
> 
> Andy Shevchenko (2):
>   iio: adc: ad4000: Check for error code from devm_mutex_init() call
>   iio: adc: pac1921: Check for error code from devm_mutex_init() call
> 
Oops. Missed this in review obviously.

Applied.
>  drivers/iio/adc/ad4000.c  | 4 +++-
>  drivers/iio/adc/pac1921.c | 4 +++-
>  2 files changed, 6 insertions(+), 2 deletions(-)
>