The definition of for_each_task() in <linux/sched.h> is based on
init_task. This symbol is exported in Linux 2.2.15 and 2.4.0-test9,
but with a comment which indicates only a special use; it is not
exported in 2.2.9.
Is there an official opinion about whether for_each_task() is intended
to be usable from a module? (Which means the older kernel is simply
buggy) or is the right way to build my own version based on "current"?