1 files changed, 9 insertions, 5 deletions

diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 358e77564e6f..1a06be61dcd0 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -2472,10 +2472,7 @@ static int cgroup_rmdir(struct inode *unused_dir, struct dentry *dentry)
                 mutex_unlock(&cgroup_mutex);
                 return -EBUSY;
         }
-
-        parent = cgrp->parent;
-        root = cgrp->root;
-        sb = root->sb;
+        mutex_unlock(&cgroup_mutex);
 
         /*
          * Call pre_destroy handlers of subsys. Notify subsystems
@@ -2483,7 +2480,14 @@ static int cgroup_rmdir(struct inode *unused_dir, struct dentry *dentry)
          */
         cgroup_call_pre_destroy(cgrp);
 
-        if (cgroup_has_css_refs(cgrp)) {
+        mutex_lock(&cgroup_mutex);
+        parent = cgrp->parent;
+        root = cgrp->root;
+        sb = root->sb;
+
+        if (atomic_read(&cgrp->count)
+            || !list_empty(&cgrp->children)
+            || cgroup_has_css_refs(cgrp)) {
                 mutex_unlock(&cgroup_mutex);
                 return -EBUSY;
         }