1 files changed, 15 insertions, 4 deletions

diff --git a/lib/rbtree.c b/lib/rbtree.c
index 12abb8abf442..d0be5fcaafe8 100644
--- a/lib/rbtree.c
+++ b/lib/rbtree.c
@@ -91,8 +91,21 @@ void rb_insert_color(struct rb_node *node, struct rb_root *root)
 {
         struct rb_node *parent, *gparent;
 
-        while ((parent = rb_parent(node)) && rb_is_red(parent))
-        {
+        while (true) {
+                /*
+                 * Loop invariant: node is red
+                 *
+                 * If there is a black parent, we are done.
+                 * Otherwise, take some corrective action as we don't
+                 * want a red root or two consecutive red nodes.
+                 */
+                parent = rb_parent(node);
+                if (!parent) {
+                        rb_set_black(node);
+                        break;
+                } else if (rb_is_black(parent))
+                        break;
+
                 gparent = rb_parent(parent);
 
                 if (parent == gparent->rb_left)
@@ -142,8 +155,6 @@ void rb_insert_color(struct rb_node *node, struct rb_root *root)
                         break;
                 }
         }
-
-        rb_set_black(root->rb_node);
 }
 EXPORT_SYMBOL(rb_insert_color);