One important point cannot be overstated: every kobject must have a
release() method, and the kobject must persist (in a consistent state)
until that method is called. If these constraints are not met, the code is
-flawed. Note that the kernel will warn you if you forget to provide a
+flawed. Note that the kernel will warn you if you forget to provide a
release() method. Do not try to get rid of this warning by providing an
-"empty" release function; you will be mocked mercilessly by the kobject
-maintainer if you attempt this.
+"empty" release function.
+
+If all your cleanup function needs to do is call kfree(), then you must
+create a wrapper function which uses container_of() to upcast to the correct
+type (as shown in the example above) and then calls kfree() on the overall
+structure.
Note, the name of the kobject is available in the release function, but it
must NOT be changed within this callback. Otherwise there will be a memory