From: Jordan Hand <jorhand@xxxxxxxxxxxxxxxxxxx>
If a child swnode is unregistered after it's parent, it can lead to
undefined behavior.
When a swnode is unregistered, recursively free it's children to avoid
this condition.
Signed-off-by: Jordan Hand <jorhand@xxxxxxxxxxxxxxxxxxx>
---
drivers/base/swnode.c | 13 ++++++++-----
1 file changed, 8 insertions(+), 5 deletions(-)
diff --git a/drivers/base/swnode.c b/drivers/base/swnode.c
index e5eb27375416..e63093b1542b 100644
--- a/drivers/base/swnode.c
+++ b/drivers/base/swnode.c
@@ -619,6 +619,8 @@ static void software_node_release(struct kobject *kobj)
property_entries_free(swnode->node->properties);
kfree(swnode->node);
}
+
+ list_del(&kobj->entry);
ida_destroy(&swnode->child_ids);
kfree(swnode);
}
@@ -712,11 +714,6 @@ EXPORT_SYMBOL_GPL(software_node_register_nodes);
* @nodes: Zero terminated array of software nodes to be unregistered
*
* Unregister multiple software nodes at once.
- *
- * NOTE: Be careful using this call if the nodes had parent pointers set up in
- * them before registering. If so, it is wiser to remove the nodes
- * individually, in the correct order (child before parent) instead of relying
- * on the sequential order of the list of nodes in the array.
*/
void software_node_unregister_nodes(const struct software_node *nodes)
{
@@ -839,10 +836,16 @@ EXPORT_SYMBOL_GPL(fwnode_create_software_node);
void fwnode_remove_software_node(struct fwnode_handle *fwnode)
{
struct swnode *swnode = to_swnode(fwnode);
+ struct swnode *child = NULL;
if (!swnode)
return;
+ while (!list_empty(&swnode->children)) {
+ child = list_first_entry_or_null(&swnode->children, struct swnode, entry);
+ fwnode_remove_software_node(&child->fwnode);
+ }
+
kobject_put(&swnode->kobj);
}
EXPORT_SYMBOL_GPL(fwnode_remove_software_node);
--
2.17.1
