[PATCH v2 3/3] cgroup: fix a race between cgroup_mount() and cgroup_kill_sb()

We've converted cgroup to kernfs so cgroup won't be intertwined with vfs objects and locking, but there are dark areas. Run two instances of this script concurrently: for ((; ;)) { mount -t cgroup -o cpuacct xxx /cgroup umount /cgroup } After a while, I saw two mount

[PATCH v2 3/3] cgroup: fix a race between cgroup_mount() and cgroup_kill_sb()

We've converted cgroup to kernfs so cgroup won't be intertwined with vfs objects and locking, but there are dark areas. Run two instances of this script concurrently: for ((; ;)) { mount -t cgroup -o cpuacct xxx /cgroup umount /cgroup } After a while, I saw two mount