Code looks like this:
@Override
protected void update(InstanceIdentifier<BoundServices> key, BoundServices boundServiceOld,
BoundServices boundServiceNew) {
LOG.error("Service Binding entry update not allowed for: {}, Data: {}",
InstanceIdentifier.keyOf(key.firstIdentifierOf(ServicesInfo.class)).getInterfaceName(),
boundServiceNew);
}

update() from MD-SAL can be called spuriously with THE SAME old and new entity. Should check that this is not the case before writing ERROR to log. From the javadoc of DataTreeChangeListener:
"
A data change event may be triggered spuriously, e.g. such that data before

• and after compare as equal. Implementations of this interface are expected
• to recover from such events. Event producers are expected to exert reasonable
• effort to suppress such events.
  "