2019-02-04 10:09:41

by Neil Armstrong

Subject: [PATCH] soc: amlogic: canvas: Fix meson_canvas_get when probe failed

When probe fails, a platforn_device is still associated to the node,
but dev_get_drvdata() returns NULL.

Handle this case by returning a consistent error.

Fixes: d4983983d987 ("soc: amlogic: add meson-canvas driver")
Signed-off-by: Neil Armstrong <[email protected]>
---
drivers/soc/amlogic/meson-canvas.c | 13 ++++++++++++-
1 file changed, 12 insertions(+), 1 deletion(-)

This fix depends on "soc: amlogic: add missing of_node_put()" at [1]

[1] https://patchwork.kernel.org/patch/10794545/

diff --git a/drivers/soc/amlogic/meson-canvas.c b/drivers/soc/amlogic/meson-canvas.c
index 87a6c6e23591..151aa84bc593 100644
--- a/drivers/soc/amlogic/meson-canvas.c
+++ b/drivers/soc/amlogic/meson-canvas.c
@@ -51,6 +51,7 @@ struct meson_canvas *meson_canvas_get(struct device *dev)
{
struct device_node *canvas_node;
struct platform_device *canvas_pdev;
+ struct meson_canvas *canvas;

canvas_node = of_parse_phandle(dev->of_node, "amlogic,canvas", 0);
if (!canvas_node)
@@ -63,7 +64,17 @@ struct meson_canvas *meson_canvas_get(struct device *dev)
}

of_node_put(canvas_node);
- return dev_get_drvdata(&canvas_pdev->dev);
+
+ /*
+ * If priv is NULL, it's probably because the canvas hasn't
+ * properly initialized. Bait out with -EINVAL because, in the
+ * current state, this driver probe cannot return -EPROBE_DEFER
+ */
+ canvas = dev_get_drvdata(&canvas_pdev->dev);
+ if (!canvas)
+ return ERR_PTR(-EINVAL);
+
+ return canvas;
}
EXPORT_SYMBOL_GPL(meson_canvas_get);

--
2.20.1

2019-02-04 10:10:24

by Maxime Jourdan

Subject: Re: [PATCH] soc: amlogic: canvas: Fix meson_canvas_get when probe failed

Hi Neil,
On Mon, Feb 4, 2019 at 10:49 AM Neil Armstrong <[email protected]> wrote:
>
> When probe fails, a platforn_device is still associated to the node,
> but dev_get_drvdata() returns NULL.
>
> Handle this case by returning a consistent error.
>
> Fixes: d4983983d987 ("soc: amlogic: add meson-canvas driver")
> Signed-off-by: Neil Armstrong <[email protected]>
> ---
> drivers/soc/amlogic/meson-canvas.c | 13 ++++++++++++-
> 1 file changed, 12 insertions(+), 1 deletion(-)
>
> This fix depends on "soc: amlogic: add missing of_node_put()" at [1]
>
> [1] https://patchwork.kernel.org/patch/10794545/
>
> diff --git a/drivers/soc/amlogic/meson-canvas.c b/drivers/soc/amlogic/meson-canvas.c
> index 87a6c6e23591..151aa84bc593 100644
> --- a/drivers/soc/amlogic/meson-canvas.c
> +++ b/drivers/soc/amlogic/meson-canvas.c
> @@ -51,6 +51,7 @@ struct meson_canvas *meson_canvas_get(struct device *dev)
> {
> struct device_node *canvas_node;
> struct platform_device *canvas_pdev;
> + struct meson_canvas *canvas;
>
> canvas_node = of_parse_phandle(dev->of_node, "amlogic,canvas", 0);
> if (!canvas_node)
> @@ -63,7 +64,17 @@ struct meson_canvas *meson_canvas_get(struct device *dev)
> }
>
> of_node_put(canvas_node);
> - return dev_get_drvdata(&canvas_pdev->dev);
> +
> + /*
> + * If priv is NULL, it's probably because the canvas hasn't
> + * properly initialized. Bait out with -EINVAL because, in the

Bait -> Bail ?

> + * current state, this driver probe cannot return -EPROBE_DEFER
> + */
> + canvas = dev_get_drvdata(&canvas_pdev->dev);
> + if (!canvas)
> + return ERR_PTR(-EINVAL);
> +
> + return canvas;
> }
> EXPORT_SYMBOL_GPL(meson_canvas_get);
>
> --
> 2.20.1
>
>
> _______________________________________________
> linux-arm-kernel mailing list
> [email protected]
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

Thanks for the patch, I missed the fact that a driver could have a
pdev yet with a failed probe.

Reviewed-by: Maxime Jourdan <[email protected]>

2019-02-08 00:31:50

by Kevin Hilman

Subject: Re: [PATCH] soc: amlogic: canvas: Fix meson_canvas_get when probe failed

Maxime Jourdan <[email protected]> writes:

> On Mon, Feb 4, 2019 at 10:49 AM Neil Armstrong <[email protected]> wrote:
>>
>> When probe fails, a platforn_device is still associated to the node,
>> but dev_get_drvdata() returns NULL.
>>
>> Handle this case by returning a consistent error.
>>
>> Fixes: d4983983d987 ("soc: amlogic: add meson-canvas driver")
>> Signed-off-by: Neil Armstrong <[email protected]>
>> ---
>> drivers/soc/amlogic/meson-canvas.c | 13 ++++++++++++-
>> 1 file changed, 12 insertions(+), 1 deletion(-)
>>
>> This fix depends on "soc: amlogic: add missing of_node_put()" at [1]
>>
>> [1] https://patchwork.kernel.org/patch/10794545/
>>
>> diff --git a/drivers/soc/amlogic/meson-canvas.c b/drivers/soc/amlogic/meson-canvas.c
>> index 87a6c6e23591..151aa84bc593 100644
>> --- a/drivers/soc/amlogic/meson-canvas.c
>> +++ b/drivers/soc/amlogic/meson-canvas.c
>> @@ -51,6 +51,7 @@ struct meson_canvas *meson_canvas_get(struct device *dev)
>> {
>> struct device_node *canvas_node;
>> struct platform_device *canvas_pdev;
>> + struct meson_canvas *canvas;
>>
>> canvas_node = of_parse_phandle(dev->of_node, "amlogic,canvas", 0);
>> if (!canvas_node)
>> @@ -63,7 +64,17 @@ struct meson_canvas *meson_canvas_get(struct device *dev)
>> }
>>
>> of_node_put(canvas_node);
>> - return dev_get_drvdata(&canvas_pdev->dev);
>> +
>> + /*
>> + * If priv is NULL, it's probably because the canvas hasn't
>> + * properly initialized. Bait out with -EINVAL because, in the
>
> Bait -> Bail ?

Fixed this up locally.

[...]

> Thanks for the patch, I missed the fact that a driver could have a
> pdev yet with a failed probe.
>
> Reviewed-by: Maxime Jourdan <[email protected]>

Queud for v5.1 with Maxime's tag. (branch: v5.1/drivers)

Kevin