| Message ID | 20250207013117.104205-2-zhangzekun11@huawei.com |
|---|---|
| State | New |
| Headers | show |
| Series | [1/9] of: Add warpper function of_find_node_by_name_balanced() | expand |
On Fri, Feb 07, 2025 at 05:37:22PM +0200, Laurent Pinchart wrote: > I'm tempted to then rename of_find_node_by_name() to > __of_find_node_by_name() to indicate it's an internal function not meant > to be called except in special cases. It could all be renamed to > __of_find_next_node_by_name() to make its behaviour clearer. > Adding "next" to the name would help a lot. Joe Hattori was finding some of these bugs using his static checker. We could easily write something really specific to find this sort of bug using Smatch. If you have ideas like this feel free to ask on smatch@vger.kernel.org. It doesn't find anything that your grep didn't find but any new bugs will be detected when they're introduced. regards, dan carpenter drivers/net/ethernet/broadcom/asp2/bcmasp.c:1370 bcmasp_probe() warn: 'dev->of_node' was not incremented drivers/net/pse-pd/tps23881.c:505 tps23881_get_of_channels() warn: 'priv->np' was not incremented drivers/media/platform/qcom/venus/core.c:301 venus_add_video_core() warn: 'dev->of_node' was not incremented drivers/regulator/tps6594-regulator.c:618 tps6594_regulator_probe() warn: 'tps->dev->of_node' was not incremented
diff --git a/include/linux/of.h b/include/linux/of.h index eaf0e2a2b75c..b7c6d7ff278c 100644 --- a/include/linux/of.h +++ b/include/linux/of.h @@ -268,6 +268,11 @@ static inline const char *of_node_full_name(const struct device_node *np) #define for_each_of_allnodes(dn) for_each_of_allnodes_from(NULL, dn) extern struct device_node *of_find_node_by_name(struct device_node *from, const char *name); +static inline struct device_node *of_find_node_by_name_balanced(struct device_node *from, + const char *name) +{ + return of_find_node_by_name(of_node_get(from), name); +} extern struct device_node *of_find_node_by_type(struct device_node *from, const char *type); extern struct device_node *of_find_compatible_node(struct device_node *from,
There are many drivers use of_find_node_by_name() with a not-NULL device_node pointer, and a number of callers would require a call to of_node_get() before using it. There are also some drivers who forget to call of_node_get() which would cause a ref count leak[1]. So, Add a wraper function for of_find_node_by_name(), drivers may use this function to call of_find_node_by_name() with the refcount already balanced. [1] https://lore.kernel.org/all/20241024015909.58654-1-zhangzekun11@huawei.com/ Signed-off-by: Zhang Zekun <zhangzekun11@huawei.com> --- include/linux/of.h | 5 +++++ 1 file changed, 5 insertions(+)