[Patch v3 1/3] maple_tree: Fix mt_destroy_walk() on root leaf node

[Wei Yang <richard.weiyang@gmail.com>]

On destroy, we should set each node dead. But current code miss this
when the maple tree has only the root node.

The reason is mt_destroy_walk() leverage mte_destroy_descend() to set
node dead, but this is skipped since the only root node is a leaf.

Fixes this by setting the node dead if it is a leaf.

Fixes: 54a611b60590 ("Maple Tree: add new data structure")
Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Cc: Liam R. Howlett <Liam.Howlett@Oracle.com>
Cc: <stable@vger.kernel.org>
Reviewed-by: Liam R. Howlett <Liam.Howlett@Oracle.com>

---
v2:
  * move the operation into mt_destroy_walk()
  * adjust the title accordingly
---
 lib/maple_tree.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/lib/maple_tree.c b/lib/maple_tree.c
index affe979bd14d..b0c345b6e646 100644
--- a/lib/maple_tree.c
+++ b/lib/maple_tree.c
@@ -5319,6 +5319,7 @@ static void mt_destroy_walk(struct maple_enode *enode, struct maple_tree *mt,
 	struct maple_enode *start;
 
 	if (mte_is_leaf(enode)) {
+		mte_set_node_dead(enode);
 		node->type = mte_node_type(enode);
 		goto free_leaf;
 	}
-- 
2.34.1