diff --git a/build/tools/merge_dtbs.py b/build/tools/merge_dtbs.py
index 74effc1b..d6468d2e 100755
--- a/build/tools/merge_dtbs.py
+++ b/build/tools/merge_dtbs.py
@@ -473,7 +473,7 @@ def create_adjacency(devicetrees):
 
 	for dt in devicetrees:
 		for symbol in dt.list_props('/__symbols__'):
-			symbol_map.setdefault(symbol, []).append(dt.filename)
+			symbol_map.setdefault(symbol, []).append(dt)
 
 	for dt in devicetrees:
 		graph[dt.filename] = set()
@@ -482,7 +482,10 @@ def create_adjacency(devicetrees):
 			if fixup not in symbol_map:
 				continue
 
-			graph[dt.filename].update(symbol_map[fixup])
+			for symbol_dt in symbol_map[fixup]:
+				if dt == symbol_dt:
+					assert not len(graph[dt.filename])
+					graph[dt.filename].add(symbol_dt)
 
 	return graph