1 files changed, 4 insertions, 1 deletions

diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index a5f75ac4e793..3f46165829a4 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -1780,8 +1780,11 @@ static void cgroup_kill_sb(struct super_block *sb)
          * If @root doesn't have any mounts or children, start killing it.
          * This prevents new mounts by disabling percpu_ref_tryget_live().
          * cgroup_mount() may wait for @root's release.
+         *
+         * And don't kill the default root.
          */
-        if (css_has_online_children(&root->cgrp.self))
+        if (css_has_online_children(&root->cgrp.self) ||
+            root == &cgrp_dfl_root)
                 cgroup_put(&root->cgrp);
         else
                 percpu_ref_kill(&root->cgrp.self.refcnt);