The kunit_device_register() function returns error pointers, not NULL.
Passing an error pointer to get_device() will lead to an Oops.  Also
get_device() returns the same device you passed to it.  Fix it!  ;)

Fixes: 7b7982f14315 ("regmap: kunit: Create a struct device for the regmap")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
---
 drivers/base/regmap/regmap-kunit.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/base/regmap/regmap-kunit.c b/drivers/base/regmap/regmap-kunit.c
index 44265dc2313d..9c5314785fc2 100644
--- a/drivers/base/regmap/regmap-kunit.c
+++ b/drivers/base/regmap/regmap-kunit.c
@@ -1925,10 +1925,10 @@ static int regmap_test_init(struct kunit *test)
 	test->priv = priv;
 
 	dev = kunit_device_register(test, "regmap_test");
-	priv->dev = get_device(dev);
-	if (!priv->dev)
-		return -ENODEV;
+	if (IS_ERR(dev))
+		return PTR_ERR(dev);
 
+	priv->dev = get_device(dev);
 	dev_set_drvdata(dev, test);
 
 	return 0;
-- 
2.43.0

On Mon, 15 Apr 2024 13:34:54 +0300, Dan Carpenter wrote:
> The kunit_device_register() function returns error pointers, not NULL.
> Passing an error pointer to get_device() will lead to an Oops.  Also
> get_device() returns the same device you passed to it.  Fix it!  ;)
> 
> 

Applied to

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap.git for-next

Thanks!

[1/1] regmap: kunit: Fix an NULL vs IS_ERR() check
      commit: 991b5e2aad870828669ca105f424ef1b2534f820

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark

> The kunit_device_register() function returns error pointers, not NULL.
> Passing an error pointer to get_device() will lead to an Oops.  Also
> get_device() returns the same device you passed to it. …

How do you think about to convert this adjustment into a patch series
with two update steps?
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/process/submitting-patches.rst?h=v6.9-rc4#n81

Regards,
Markus

On 15/04/2024 11:34, Dan Carpenter wrote:
> The kunit_device_register() function returns error pointers, not NULL.
> Passing an error pointer to get_device() will lead to an Oops.  Also
> get_device() returns the same device you passed to it.  Fix it!  ;)
> 
> Fixes: 7b7982f14315 ("regmap: kunit: Create a struct device for the regmap")
> Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
> ---
>   drivers/base/regmap/regmap-kunit.c | 6 +++---
>   1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/base/regmap/regmap-kunit.c b/drivers/base/regmap/regmap-kunit.c
> index 44265dc2313d..9c5314785fc2 100644
> --- a/drivers/base/regmap/regmap-kunit.c
> +++ b/drivers/base/regmap/regmap-kunit.c
> @@ -1925,10 +1925,10 @@ static int regmap_test_init(struct kunit *test)
>   	test->priv = priv;
>   
>   	dev = kunit_device_register(test, "regmap_test");
> -	priv->dev = get_device(dev);
> -	if (!priv->dev)
> -		return -ENODEV;
> +	if (IS_ERR(dev))
> +		return PTR_ERR(dev);
>   
> +	priv->dev = get_device(dev);
>   	dev_set_drvdata(dev, test);
>   
>   	return 0;

Reviewed-by: Richard Fitzgerald <rf@opensource.cirrus.com>