Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
MIME-Version: 1.0
References: <20201127094445.121232-1-miaoqinglang@huawei.com>
In-Reply-To: <20201127094445.121232-1-miaoqinglang@huawei.com>
From:   Bartosz Golaszewski <bgolaszewski@baylibre.com>
Date:   Wed, 2 Dec 2020 10:45:37 +0100
Message-ID: <CAMpxmJXww=a3HoKcGvKQ3M2K6kAO0KGfyB9aCKbG+E_F_0iq7A@mail.gmail.com>
Subject: Re: [PATCH] gpio: zynq: fix reference leak in zynq_gpio functions
To:     Qinglang Miao <miaoqinglang@huawei.com>
Cc:     Linus Walleij <linus.walleij@linaro.org>,
        Michal Simek <michal.simek@xilinx.com>,
        linux-gpio <linux-gpio@vger.kernel.org>,
        arm-soc <linux-arm-kernel@lists.infradead.org>,
        LKML <linux-kernel@vger.kernel.org>
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

On Fri, Nov 27, 2020 at 10:40 AM Qinglang Miao <miaoqinglang@huawei.com> 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@huawei.com>
> Signed-off-by: Qinglang Miao <miaoqinglang@huawei.com>
> ---
>  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