3 files changed, 12 insertions, 6 deletions

diff --git a/include/linux/freezer.h b/include/linux/freezer.h
index 5a361f85cfec..da7e52b099f3 100644
--- a/include/linux/freezer.h
+++ b/include/linux/freezer.h
@@ -64,9 +64,12 @@ extern bool freeze_task(struct task_struct *p, bool sig_only);
 extern void cancel_freezing(struct task_struct *p);
 
 #ifdef CONFIG_CGROUP_FREEZER
-extern int cgroup_frozen(struct task_struct *task);
+extern int cgroup_freezing_or_frozen(struct task_struct *task);
 #else /* !CONFIG_CGROUP_FREEZER */
-static inline int cgroup_frozen(struct task_struct *task) { return 0; }
+static inline int cgroup_freezing_or_frozen(struct task_struct *task)
+{
+        return 0;
+}
 #endif /* !CONFIG_CGROUP_FREEZER */
 
 /*
diff --git a/kernel/cgroup_freezer.c b/kernel/cgroup_freezer.c
index 59e9ef6aab40..eb3f34d57419 100644
--- a/kernel/cgroup_freezer.c
+++ b/kernel/cgroup_freezer.c
@@ -47,17 +47,20 @@ static inline struct freezer *task_freezer(struct task_struct *task)
                             struct freezer, css);
 }
 
-int cgroup_frozen(struct task_struct *task)
+int cgroup_freezing_or_frozen(struct task_struct *task)
 {
         struct freezer *freezer;
         enum freezer_state state;
 
         task_lock(task);
         freezer = task_freezer(task);
-        state = freezer->state;
+        if (!freezer->css.cgroup->parent)
+                state = CGROUP_THAWED; /* root cgroup can't be frozen */
+        else
+                state = freezer->state;
         task_unlock(task);
 
-        return state == CGROUP_FROZEN;
+        return (state == CGROUP_FREEZING) || (state == CGROUP_FROZEN);
 }
 
 /*
diff --git a/kernel/power/process.c b/kernel/power/process.c
index a0480cd4daaf..71ae29052ab6 100644
--- a/kernel/power/process.c
+++ b/kernel/power/process.c
@@ -144,7 +144,7 @@ static void thaw_tasks(bool nosig_only)
                 if (nosig_only && should_send_signal(p))
                         continue;
 
-                if (cgroup_frozen(p))
+                if (cgroup_freezing_or_frozen(p))
                         continue;
 
                 thaw_process(p);