On Fri, Oct 11, 2024 at 6:20 PM Fabrizio Castro
<fabrizio.castro.jz@xxxxxxxxxxx> wrote:
>
> rzg2l_irqc_common_init calls of_find_device_by_node, but the
> corresponding put_device call is missing.
> This also gets reported by make coccicheck.
>
> Make use of the cleanup interfaces from cleanup.h to call into
> __free_put_device (which in turn calls into put_device) when
> leaving function rzg2l_irqc_common_init and variable "dev" goes
> out of scope.
>
> Mind that we don't want to "put" "dev" when rzg2l_irqc_common_init
> completes successfully, therefore assign NULL to "dev" to prevent
> __free_put_device from calling into put_device within the successful
> path.
>
> "make coccicheck" will still complain about missing put_device calls,
> but those are false positives now.
>
> Fixes: 3fed09559cd8 ("irqchip: Add RZ/G2L IA55 Interrupt Controller driver")
> Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@xxxxxxxxxxx>
> ---
>
> v3->v4:
> * switched to using the cleanup interfaces as an alternative to using
> goto chains
>
> drivers/irqchip/irq-renesas-rzg2l.c | 16 ++++++++++++++--
> 1 file changed, 14 insertions(+), 2 deletions(-)
>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
Cheers,
Prabhakar
> diff --git a/drivers/irqchip/irq-renesas-rzg2l.c b/drivers/irqchip/irq-renesas-rzg2l.c
> index 693ff285ca2c..99e27e01b0b1 100644
> --- a/drivers/irqchip/irq-renesas-rzg2l.c
> +++ b/drivers/irqchip/irq-renesas-rzg2l.c
> @@ -8,6 +8,7 @@
> */
>
> #include <linux/bitfield.h>
> +#include <linux/cleanup.h>
> #include <linux/clk.h>
> #include <linux/err.h>
> #include <linux/io.h>
> @@ -530,12 +531,12 @@ static int rzg2l_irqc_parse_interrupts(struct rzg2l_irqc_priv *priv,
> static int rzg2l_irqc_common_init(struct device_node *node, struct device_node *parent,
> const struct irq_chip *irq_chip)
> {
> + struct platform_device *pdev = of_find_device_by_node(node);
> + struct device *dev __free(put_device) = pdev ? &pdev->dev : NULL;
> struct irq_domain *irq_domain, *parent_domain;
> - struct platform_device *pdev;
> struct reset_control *resetn;
> int ret;
>
> - pdev = of_find_device_by_node(node);
> if (!pdev)
> return -ENODEV;
>
> @@ -591,6 +592,17 @@ static int rzg2l_irqc_common_init(struct device_node *node, struct device_node *
>
> register_syscore_ops(&rzg2l_irqc_syscore_ops);
>
> + /*
> + * Prevent the cleanup function from invoking put_device by assigning
> + * NULL to dev.
> + *
> + * make coccicheck will complain about missing put_device calls, but
> + * those are false positives, as dev will be automatically "put" via
> + * __free_put_device on the failing path.
> + * On the successful path we don't actually want to "put" dev.
> + */
> + dev = NULL;
> +
> return 0;
>
> pm_put:
> --
> 2.34.1
>
>
