rzg2l_irqc_common_init calls of_find_device_by_node, but the
corresponding put_device call is missing.

Make sure we call put_device when failing.

"make coccicheck" will complain about a missing put_device before
successfully returning from rzg2l_irqc_common_init, however, that's
a false positive.

Fixes: 3fed09559cd8 ("irqchip: Add RZ/G2L IA55 Interrupt Controller driver")
Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
---

v2->v3:
* Fixed typo in commit log (rzv2h_icu_init replaced with rzg2l_irqc_common_init).

v1->v2:
* Dropped put_device from the successful path, and added a comment to prevent
  others from acting upon make coccicheck output.

 drivers/irqchip/irq-renesas-rzg2l.c | 32 +++++++++++++++++++++--------
 1 file changed, 23 insertions(+), 9 deletions(-)

diff --git a/drivers/irqchip/irq-renesas-rzg2l.c b/drivers/irqchip/irq-renesas-rzg2l.c
index 693ff285ca2c..040463e3b39c 100644
--- a/drivers/irqchip/irq-renesas-rzg2l.c
+++ b/drivers/irqchip/irq-renesas-rzg2l.c
@@ -542,33 +542,40 @@ static int rzg2l_irqc_common_init(struct device_node *node, struct device_node *
 	parent_domain = irq_find_host(parent);
 	if (!parent_domain) {
 		dev_err(&pdev->dev, "cannot find parent domain\n");
-		return -ENODEV;
+		ret = -ENODEV;
+		goto put_dev;
 	}
 
 	rzg2l_irqc_data = devm_kzalloc(&pdev->dev, sizeof(*rzg2l_irqc_data), GFP_KERNEL);
-	if (!rzg2l_irqc_data)
-		return -ENOMEM;
+	if (!rzg2l_irqc_data) {
+		ret = -ENOMEM;
+		goto put_dev;
+	}
 
 	rzg2l_irqc_data->irqchip = irq_chip;
 
 	rzg2l_irqc_data->base = devm_of_iomap(&pdev->dev, pdev->dev.of_node, 0, NULL);
-	if (IS_ERR(rzg2l_irqc_data->base))
-		return PTR_ERR(rzg2l_irqc_data->base);
+	if (IS_ERR(rzg2l_irqc_data->base)) {
+		ret = PTR_ERR(rzg2l_irqc_data->base);
+		goto put_dev;
+	}
 
 	ret = rzg2l_irqc_parse_interrupts(rzg2l_irqc_data, node);
 	if (ret) {
 		dev_err(&pdev->dev, "cannot parse interrupts: %d\n", ret);
-		return ret;
+		goto put_dev;
 	}
 
 	resetn = devm_reset_control_get_exclusive(&pdev->dev, NULL);
-	if (IS_ERR(resetn))
-		return PTR_ERR(resetn);
+	if (IS_ERR(resetn)) {
+		ret = PTR_ERR(resetn);
+		goto put_dev;
+	}
 
 	ret = reset_control_deassert(resetn);
 	if (ret) {
 		dev_err(&pdev->dev, "failed to deassert resetn pin, %d\n", ret);
-		return ret;
+		goto put_dev;
 	}
 
 	pm_runtime_enable(&pdev->dev);
@@ -591,6 +598,10 @@ static int rzg2l_irqc_common_init(struct device_node *node, struct device_node *
 
 	register_syscore_ops(&rzg2l_irqc_syscore_ops);
 
+	/*
+	 * coccicheck complains about a missing put_device call before returning, but it's a false
+	 * positive. We still need &pdev->dev after successfully returning from this function.
+	 */
 	return 0;
 
 pm_put:
@@ -598,6 +609,9 @@ static int rzg2l_irqc_common_init(struct device_node *node, struct device_node *
 pm_disable:
 	pm_runtime_disable(&pdev->dev);
 	reset_control_assert(resetn);
+put_dev:
+	put_device(&pdev->dev);
+
 	return ret;
 }
 
-- 
2.34.1

> rzg2l_irqc_common_init calls of_find_device_by_node, but the
> corresponding put_device call is missing.
>
> Make sure we call put_device when failing.
>
> "make coccicheck" will complain about a missing put_device before
> successfully returning from rzg2l_irqc_common_init, however, that's
> a false positive.
>
> Fixes: 3fed09559cd8 ("irqchip: Add RZ/G2L IA55 Interrupt Controller driver")

Might the application of scope-based resource management become more
interesting accordingly?

Regards,
Markus

Hi Markus,

On Thu, Oct 10, 2024 at 7:53 PM Markus Elfring <Markus.Elfring@web.de> wrote:
> > rzg2l_irqc_common_init calls of_find_device_by_node, but the
> > corresponding put_device call is missing.
> >
> > Make sure we call put_device when failing.
> >
> > "make coccicheck" will complain about a missing put_device before
> > successfully returning from rzg2l_irqc_common_init, however, that's
> > a false positive.
> >
> > Fixes: 3fed09559cd8 ("irqchip: Add RZ/G2L IA55 Interrupt Controller driver")
>
> Might the application of scope-based resource management become more
> interesting accordingly?

No, as explained in the comments:

> > +       /*
> > +        * coccicheck complains about a missing put_device call before returning, but it's a false
> > +        * positive. We still need &pdev->dev after successfully returning from this function.
> > +        */

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

>>> rzg2l_irqc_common_init calls of_find_device_by_node, but the
>>> corresponding put_device call is missing.
>>>
>>> Make sure we call put_device when failing.
>>>
>>> "make coccicheck" will complain about a missing put_device before
>>> successfully returning from rzg2l_irqc_common_init, however, that's
>>> a false positive.
>>>
>>> Fixes: 3fed09559cd8 ("irqchip: Add RZ/G2L IA55 Interrupt Controller driver")
>>
>> Might the application of scope-based resource management become more
>> interesting accordingly?
>
> No, as explained in the comments:
>
>>> +       /*
>>> +        * coccicheck complains about a missing put_device call before returning, but it's a false
>>> +        * positive. We still need &pdev->dev after successfully returning from this function.
>>> +        */

Please reconsider the applicability of mentioned programming interfaces once more
(as an evolving software design alternative for goto chains).
https://elixir.bootlin.com/linux/v6.12-rc2/source/include/linux/device.h#L1239

Regards,
Markus