Hello, Sorry for delay and for confusing you in our previous discussion here https://lore.kernel.org/all/20240610105028.GA21586@xxxxxxxxxx/ No, cgroup_exit() can't rely on group_dead, this is racy. And no, we can't shift css_set_skip_task_iters/etc from cgroup_release() to cgroup_exit(), an execing sub-thread can change the group leader. Let me at least send the simple patch which looks "obviously good" to me. I would really like to remove the usage of signal->live in cgroup.c, but so far I do not see a simple solution. With or without this change cgroup.procs can be empty but cgroup.threads is not. But at least the exiting sub-threads which have already passed atomic_dec_and_test() should call cgroup_exit() "soon". Oleg.
