Hi, We recently were hit (unnecessarily hard) when after kernel uprev we figured that something wasn't working. The root cause was a rename of the CONFIG_FOO option between kernel releases, which make oldconfig doesn't warn/notify about. Would it be possible to add either a new --listunknown mode to conf or to somehow make it conf_warning("unknown symbol: %s\n", line) when it reads a line from oldconf that it cannot sym_find()? That would save a ton of time.