2020-06-02 04:58:12

by Navid Emamdoost

Subject: [PATCH] spi: tegra114: missing put on pm_runtime_get_sync failure

the call to pm_runtime_get_sync increments the counter even
in case of failure leading to incorrect ref count.
Call pm_runtime_put if pm_runtime_get_sync fails.

Signed-off-by: Navid Emamdoost <[email protected]>
---
drivers/spi/spi-tegra114.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/spi/spi-tegra114.c b/drivers/spi/spi-tegra114.c
index 83edabdb41ad..dccd2ac1a975 100644
--- a/drivers/spi/spi-tegra114.c
+++ b/drivers/spi/spi-tegra114.c
@@ -974,6 +974,7 @@ static int tegra_spi_setup(struct spi_device *spi)
dev_err(tspi->dev, "pm runtime failed, e = %d\n", ret);
if (cdata)
tegra_spi_cleanup(spi);
+ pm_runtime_put(tspi->dev);
return ret;
}

@@ -1398,6 +1399,7 @@ static int tegra_spi_probe(struct platform_device *pdev)
ret = pm_runtime_get_sync(&pdev->dev);
if (ret < 0) {
dev_err(&pdev->dev, "pm runtime get failed, e = %d\n", ret);
+ pm_runtime_put(&pdev->dev);
goto exit_pm_disable;
}

@@ -1479,6 +1481,7 @@ static int tegra_spi_resume(struct device *dev)
ret = pm_runtime_get_sync(dev);
if (ret < 0) {
dev_err(dev, "pm runtime failed, e = %d\n", ret);
+ pm_runtime_put(dev);
return ret;
}
tegra_spi_writel(tspi, tspi->command1_reg, SPI_COMMAND1);
--
2.17.1

2020-06-05 06:11:28

by Jon Hunter

Subject: Re: [PATCH] spi: tegra114: missing put on pm_runtime_get_sync failure

On 02/06/2020 05:55, Navid Emamdoost wrote:
> the call to pm_runtime_get_sync increments the counter even
> in case of failure leading to incorrect ref count.
> Call pm_runtime_put if pm_runtime_get_sync fails.
>
> Signed-off-by: Navid Emamdoost <[email protected]>
> ---
> drivers/spi/spi-tegra114.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/drivers/spi/spi-tegra114.c b/drivers/spi/spi-tegra114.c
> index 83edabdb41ad..dccd2ac1a975 100644
> --- a/drivers/spi/spi-tegra114.c
> +++ b/drivers/spi/spi-tegra114.c
> @@ -974,6 +974,7 @@ static int tegra_spi_setup(struct spi_device *spi)
> dev_err(tspi->dev, "pm runtime failed, e = %d\n", ret);
> if (cdata)
> tegra_spi_cleanup(spi);
> + pm_runtime_put(tspi->dev);
> return ret;
> }
>
> @@ -1398,6 +1399,7 @@ static int tegra_spi_probe(struct platform_device *pdev)
> ret = pm_runtime_get_sync(&pdev->dev);
> if (ret < 0) {
> dev_err(&pdev->dev, "pm runtime get failed, e = %d\n", ret);
> + pm_runtime_put(&pdev->dev);
> goto exit_pm_disable;
> }

I am wondering if it is better we use put_sync() here to ensure that
this happens before we exit the probe.

Jon

--
nvpublic

2020-06-05 06:15:55

by Navid Emamdoost

Subject: Re: [PATCH] spi: tegra114: missing put on pm_runtime_get_sync failure

On Fri, Jun 5, 2020 at 1:09 AM Jon Hunter <[email protected]> wrote:
>
>
> On 02/06/2020 05:55, Navid Emamdoost wrote:
> > the call to pm_runtime_get_sync increments the counter even
> > in case of failure leading to incorrect ref count.
> > Call pm_runtime_put if pm_runtime_get_sync fails.
> >
> > Signed-off-by: Navid Emamdoost <[email protected]>
> > ---
> > drivers/spi/spi-tegra114.c | 3 +++
> > 1 file changed, 3 insertions(+)
> >
> > diff --git a/drivers/spi/spi-tegra114.c b/drivers/spi/spi-tegra114.c
> > index 83edabdb41ad..dccd2ac1a975 100644
> > --- a/drivers/spi/spi-tegra114.c
> > +++ b/drivers/spi/spi-tegra114.c
> > @@ -974,6 +974,7 @@ static int tegra_spi_setup(struct spi_device *spi)
> > dev_err(tspi->dev, "pm runtime failed, e = %d\n", ret);
> > if (cdata)
> > tegra_spi_cleanup(spi);
> > + pm_runtime_put(tspi->dev);
> > return ret;
> > }
> >
> > @@ -1398,6 +1399,7 @@ static int tegra_spi_probe(struct platform_device *pdev)
> > ret = pm_runtime_get_sync(&pdev->dev);
> > if (ret < 0) {
> > dev_err(&pdev->dev, "pm runtime get failed, e = %d\n", ret);
> > + pm_runtime_put(&pdev->dev);
> > goto exit_pm_disable;
> > }
>
> I am wondering if it is better we use put_sync() here to ensure that
> this happens before we exit the probe.

To be honest I am not sure when to use different flavors of
pm_runtime_put (like pm_runtime_put_noidle,
pm_runtime_put_autosuspend, pm_runtime_put_sync, pm_runtime_put,
pm_runtime_put_sync_suspend). I'd appreciate it if you could give me a
pointer on how to decide on this.

>
> Jon
>
> --
> nvpublic



--
Navid.