cgroup: fix rule checking for threaded mode switching
A domain cgroup isn't allowed to be turned threaded if its subtree is populated or domain controllers are enabled. cgroup_enable_threaded() depended on cgroup_can_be_thread_root() test to enforce this rule. A parent which has populated domain descendants or have domain controllers enabled can't become a thread root, so the above rules are enforced automatically. However, for the root cgroup which can host mixed domain and threaded children, cgroup_can_be_thread_root() doesn't check any of those conditions and thus first level cgroups ends up escaping those rules. This patch fixes the bug by adding explicit checks for those rules in cgroup_enable_threaded(). Reported-by: NMichael Kerrisk (man-pages) <mtk.manpages@gmail.com> Signed-off-by: NTejun Heo <tj@kernel.org> Fixes: 8cfd8147 ("cgroup: implement cgroup v2 thread support") Cc: stable@vger.kernel.org # v4.14+
Showing
想要评论请 注册 或 登录