On Sun, Feb 02, 2020 at 10:37:02AM +0100, Christian Brauner <christian.brauner@ubuntu.com> wrote:
> cgroup_post_fork() is called past the point of no return for fork and
> cgroup_css_set_put_fork() is explicitly documented as only being
> callable before forks point of no return:
I missed this and somehow incorrectly assumed it's called at the end of
fork too. I find the css_set refcounting correct now.

BTW any reason why not to utilize cgroup_css_set_put_fork() for the
regular cleanup in cgroup_post_fork() too?

Thanks,
Michal