quoted

For example, I'm trying to fix a race. See https://lkml.org/lkml/2016/8/8/900

And the fix kind of relies on the fact that cgroup_post_fork() is placed
inside the read section of cgroup_threadgroup_rwsem, so that cpuset_fork()
won't race with cgroup migration.

My patch retains that behaviour, before ss->fork() is called we hold
the cgroup_threadgroup_rwsem, in fact it is held prior to ss->can_fork()

I read the patch again and now I see only threadgroup_change_begin() is moved
downwards, and threadgroup_change_end() remains intact. Then I have no problem
with it.

Acked-by: Zefan Li <redacted>