[PATCH 1/5] clk: add missing of_node_put

Julia Lawall
2015-10-21T20:41:36Z

for_each_matching_node_and_match performs an of_node_get on each iteration,
so a break out of the loop requires an of_node_put.

A simplified version of the semantic patch that fixes this problem is as
follows (http://coccinelle.lip6.fr):

// <smpl>
@@
expression e1,e2,e;
local idexpression np;
@@

for_each_matching_node_and_match(np, e1, e2) {
... when != of_node_put(np)
when != e = np
(
return np;
|
+ of_node_put(np);
? return ...;
)
...
}
// </smpl>

Besides the problem identified by the semantic patch, this patch adds an
of_node_get in front of saving np in a field of parent, to account for the
fact that this value will be put on going on to the next element in the
iteration, and then adds of_node_puts in the two loops where the parent
pointer can be freed.

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
drivers/clk/clk.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index e735eab..11babd1 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -3200,12 +3200,15 @@ void __init of_clk_init(const struct of_device_id *matches)
list_for_each_entry_safe(clk_provider, next,
&clk_provider_list, node) {
list_del(&clk_provider->node);
+ of_node_put(clk_provider->np);
kfree(clk_provider);
}
+ of_node_put(np);
return;
}

parent->clk_init_cb = match->data;
+ of_node_get(np);
parent->np = np;
list_add_tail(&parent->node, &clk_provider_list);
}
@@ -3220,6 +3223,7 @@ void __init of_clk_init(const struct of_device_id *matches)
of_clk_set_defaults(clk_provider->np, true);

list_del(&clk_provider->node);
+ of_node_put(clk_provider->np);
kfree(clk_provider);
is_init_done = true;
}