[POWERPC] Add a warning to help trackdown device_node refcounting bugs

[mv-sheeva.git] / arch / powerpc / kernel / prom.c

diff --git a/arch/powerpc/kernel/prom.c b/arch/powerpc/kernel/prom.c
index bcd1c5ed44a35066be85372366f9d6240c409e88..6d5e601097a0df33f65e4fca29144719915e6541 100644 (file)
--- a/arch/powerpc/kernel/prom.c
+++ b/arch/powerpc/kernel/prom.c
@@ -1375,8 +1375,17 @@ static void of_node_release(struct kref *kref)
        struct device_node *node = kref_to_device_node(kref);
        struct property *prop = node->properties;
 
+       /* We should never be releasing nodes that haven't been detached. */
+       if (!of_node_check_flag(node, OF_DETACHED)) {
+               printk("WARNING: Bad of_node_put() on %s\n", node->full_name);
+               dump_stack();
+               kref_init(&node->kref);
+               return;
+       }
+
        if (!of_node_check_flag(node, OF_DYNAMIC))
                return;
+
        while (prop) {
                struct property *next = prop->next;
                kfree(prop->name);
@@ -1457,6 +1466,8 @@ void of_detach_node(const struct device_node *np)
                prevsib->sibling = np->sibling;
        }
 
+       of_node_set_flag(np, OF_DETACHED);
+
 out_unlock:
        write_unlock(&devtree_lock);
 }