arm: add missing of_node_put
authorJulia Lawall <julia.lawall@lip6.fr>
Sat, 10 Oct 2015 21:41:42 +0000 (23:41 +0200)
committerRussell King <rmk+kernel@arm.linux.org.uk>
Mon, 26 Oct 2015 10:58:26 +0000 (10:58 +0000)
for_each_child_of_node performs an of_node_get on each iteration, so
a break out of the loop requires an of_node_put.

The of_node_put is duplicated in front of each error return, because the
function contains a later error return that is beyond the end of the
for_each_child_of_node and thus doesn't need of_node_put.

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

// <smpl>
@@
expression root,e;
local idexpression child;
iterator name for_each_child_of_node;
@@

 for_each_child_of_node(root, child) {
   ... when != of_node_put(child)
       when != e = child
(
   return child;
|
+  of_node_put(child);
?  return ...;
)
   ...
 }

@@
expression root,e;
local idexpression child;
@@

 for_each_child_of_node(root, child) {
   ... when != of_node_put(child)
       when != e = child
+  of_node_put(child);
?  break;
   ...
}
... when != child
// </smpl>

Additionally, concatenated a string in an affected line to avoid introducing
a checkpatch warning.

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
arch/arm/kernel/devtree.c

index 11c54de..65addcb 100644 (file)
@@ -101,6 +101,7 @@ void __init arm_dt_init_cpu_maps(void)
                if (of_property_read_u32(cpu, "reg", &hwid)) {
                        pr_debug(" * %s missing reg property\n",
                                     cpu->full_name);
+                       of_node_put(cpu);
                        return;
                }
 
@@ -108,8 +109,10 @@ void __init arm_dt_init_cpu_maps(void)
                 * 8 MSBs must be set to 0 in the DT since the reg property
                 * defines the MPIDR[23:0].
                 */
-               if (hwid & ~MPIDR_HWID_BITMASK)
+               if (hwid & ~MPIDR_HWID_BITMASK) {
+                       of_node_put(cpu);
                        return;
+               }
 
                /*
                 * Duplicate MPIDRs are a recipe for disaster.
@@ -119,9 +122,11 @@ void __init arm_dt_init_cpu_maps(void)
                 * to avoid matching valid MPIDR[23:0] values.
                 */
                for (j = 0; j < cpuidx; j++)
-                       if (WARN(tmp_map[j] == hwid, "Duplicate /cpu reg "
-                                                    "properties in the DT\n"))
+                       if (WARN(tmp_map[j] == hwid,
+                                "Duplicate /cpu reg properties in the DT\n")) {
+                               of_node_put(cpu);
                                return;
+                       }
 
                /*
                 * Build a stashed array of MPIDR values. Numbering scheme
@@ -143,6 +148,7 @@ void __init arm_dt_init_cpu_maps(void)
                                               "max cores %u, capping them\n",
                                               cpuidx, nr_cpu_ids)) {
                        cpuidx = nr_cpu_ids;
+                       of_node_put(cpu);
                        break;
                }