Re: [PATCH] gpio: zynq: fix reference leak in zynq_gpio functions

From: Bartosz Golaszewski
Date: Wed Dec 02 2020 - 04:46:31 EST


On Fri, Nov 27, 2020 at 10:40 AM Qinglang Miao <miaoqinglang@xxxxxxxxxx> wrote:
>
> pm_runtime_get_sync will increment pm usage counter even it
> failed. Forgetting to putting operation will result in a
> reference leak here.
>
> A new function pm_runtime_resume_and_get is introduced in
> [0] to keep usage counter balanced. So We fix the reference
> leak by replacing it with new funtion.
>
> [0] dd8088d5a896 ("PM: runtime: Add pm_runtime_resume_and_get to deal with usage counter")
>
> Fixes: c2df3de0d07e ("gpio: zynq: properly support runtime PM for GPIO used as interrupts")
> Reported-by: Hulk Robot <hulkci@xxxxxxxxxx>
> Signed-off-by: Qinglang Miao <miaoqinglang@xxxxxxxxxx>
> ---
> drivers/gpio/gpio-zynq.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpio/gpio-zynq.c b/drivers/gpio/gpio-zynq.c
> index 0b5a17ab9..3521c1dc3 100644
> --- a/drivers/gpio/gpio-zynq.c
> +++ b/drivers/gpio/gpio-zynq.c
> @@ -574,7 +574,7 @@ static int zynq_gpio_irq_reqres(struct irq_data *d)
> struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
> int ret;
>
> - ret = pm_runtime_get_sync(chip->parent);
> + ret = pm_runtime_resume_and_get(chip->parent);
> if (ret < 0)
> return ret;
>
> @@ -942,7 +942,7 @@ static int zynq_gpio_probe(struct platform_device *pdev)
>
> pm_runtime_set_active(&pdev->dev);
> pm_runtime_enable(&pdev->dev);
> - ret = pm_runtime_get_sync(&pdev->dev);
> + ret = pm_runtime_resume_and_get(&pdev->dev);
> if (ret < 0)
> goto err_pm_dis;
>
> --
> 2.23.0
>

Applied, thanks!

Bartosz