diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
index 57ff31b6b1e4..5a1b8688b460 100644
--- a/drivers/of/fdt.c
+++ b/drivers/of/fdt.c
@@ -315,7 +315,7 @@ static int unflatten_dt_nodes(const void *blob,
 	for (offset = 0;
 	     offset >= 0 && depth >= initial_depth;
 	     offset = fdt_next_node(blob, offset, &depth)) {
-		if (WARN_ON_ONCE(depth >= FDT_MAX_DEPTH))
+		if (WARN_ON_ONCE(depth >= FDT_MAX_DEPTH - 1))
 			continue;
 
 		if (!IS_ENABLED(CONFIG_OF_KOBJ) &&