Re: [PATCH 02/12] drm/tegra: rgb: add missing of_node_put after of_device_is_available

From: Mukesh Ojha
Date: Mon Apr 01 2019 - 08:49:28 EST



On 2/23/2019 6:50 PM, Julia Lawall wrote:
Add an of_node_put when a tested device node is not available.

The semantic patch that fixes this problem is as follows
(http://coccinelle.lip6.fr):

// <smpl>
@@
identifier f;
local idexpression e;
expression x;
@@

e = f(...);
... when != of_node_put(e)
when != x = e
when != e = x
when any
if (<+...of_device_is_available(e)...+>) {
... when != of_node_put(e)
(
return e;
|
+ of_node_put(e);
return ...;
)
}
// </smpl>

Fixes: d8f4a9eda0067 ("drm: Add NVIDIA Tegra20 support")
Signed-off-by: Julia Lawall <Julia.Lawall@xxxxxxx>
Reviewed-by: Mukesh Ojha <mojha@xxxxxxxxxxxxxx>

Cheers,
-Mukesh

---
drivers/gpu/drm/tegra/rgb.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff -u -p a/drivers/gpu/drm/tegra/rgb.c b/drivers/gpu/drm/tegra/rgb.c
--- a/drivers/gpu/drm/tegra/rgb.c
+++ b/drivers/gpu/drm/tegra/rgb.c
@@ -221,8 +221,10 @@ int tegra_dc_rgb_probe(struct tegra_dc *
int err;
np = of_get_child_by_name(dc->dev->of_node, "rgb");
- if (!np || !of_device_is_available(np))
+ if (!np || !of_device_is_available(np)) {
+ of_node_put(np);
return -ENODEV;
+ }
rgb = devm_kzalloc(dc->dev, sizeof(*rgb), GFP_KERNEL);
if (!rgb)