of: unittest: allow base devicetree to have symbol metadata

The overlay metadata nodes in the FDT created from testcases.dts
are not handled properly.

The __fixups__ and __local_fixups__ node were added to the live
devicetree, but should not be.

Only the first property in the /__symbols__ node was added to the
live devicetree if the live devicetree already contained a
/__symbols node.  All of the node's properties must be added.
Tested-by: Alan Tull <atull@kernel.org>
Signed-off-by: Frank Rowand <frank.rowand@sony.com>

drivers/of/unittest.c

@@ -1071,20 +1071,44 @@ static void __init of_unittest_platform_populate(void)
  *	of np into dup node (present in live tree) and
  *	updates parent of children of np to dup.
  *
- *	@np:	node already present in live tree
+ *	@np:	node whose properties are being added to the live tree
  *	@dup:	node present in live tree to be updated
  */
 static void update_node_properties(struct device_node *np,
 					struct device_node *dup)
 {
 	struct property *prop;
+	struct property *save_next;
 	struct device_node *child;
-
-	for_each_property_of_node(np, prop)
-		of_add_property(dup, prop);
+	int ret;
 
 	for_each_child_of_node(np, child)
 		child->parent = dup;
+
+	/*
+	 * "unittest internal error: unable to add testdata property"
+	 *
+	 *    If this message reports a property in node '/__symbols__' then
+	 *    the respective unittest overlay contains a label that has the
+	 *    same name as a label in the live devicetree.  The label will
+	 *    be in the live devicetree only if the devicetree source was
+	 *    compiled with the '-@' option.  If you encounter this error,
+	 *    please consider renaming __all__ of the labels in the unittest
+	 *    overlay dts files with an odd prefix that is unlikely to be
+	 *    used in a real devicetree.
+	 */
+
+	/*
+	 * open code for_each_property_of_node() because of_add_property()
+	 * sets prop->next to NULL
+	 */
+	for (prop = np->properties; prop != NULL; prop = save_next) {
+		save_next = prop->next;
+		ret = of_add_property(dup, prop);
+		if (ret)
+			pr_err("unittest internal error: unable to add testdata property %pOF/%s",
+			       np, prop->name);
+	}
 }
 
 /**
@@ -1093,18 +1117,23 @@ static void update_node_properties(struct device_node *np,
  *
  *	@np:	Node to attach to live tree
  */
-static int attach_node_and_children(struct device_node *np)
+static void attach_node_and_children(struct device_node *np)
 {
 	struct device_node *next, *dup, *child;
 	unsigned long flags;
 	const char *full_name;
 
 	full_name = kasprintf(GFP_KERNEL, "%pOF", np);
+
+	if (!strcmp(full_name, "/__local_fixups__") ||
+	    !strcmp(full_name, "/__fixups__"))
+		return;
+
 	dup = of_find_node_by_path(full_name);
 	kfree(full_name);
 	if (dup) {
 		update_node_properties(np, dup);
-		return 0;
+		return;
 	}
 
 	child = np->child;
@@ -1125,8 +1154,6 @@ static int attach_node_and_children(struct device_node *np)
 		attach_node_and_children(child);
 		child = next;
 	}
-
-	return 0;
 }
 
 /**