calls. At the moment they only require CAP_SYS_BOOT capability, but more can be
added later.
+2.4.8 KF_RCU flag
+-----------------
+
+The KF_RCU flag is used for kfuncs which have a rcu ptr as its argument.
+When used together with KF_ACQUIRE, it indicates the kfunc should have a
+single argument which must be a trusted argument or a MEM_RCU pointer.
+The argument may have reference count of 0 and the kfunc must take this
+into consideration.
+
2.5 Registering the kfuncs
--------------------------