1. In a data processing device comprising a processor unit coupled to a cache comprising a plurality of cache lines, a method comprising: setting a lockout indicator in response to detecting an error at data stored at a first cache line of the plurality of cache lines; determining a lockout policy based on stored information; in response to determining the lockout policy is a first policy, maintaining the lockout indicator for the first cache line in the first state in response to a cache invalidation event; and in response to determining the lockout policy is a second policy, setting the lockout indicator for the first cache line to a second state in response to the cache invalidation event.