1 files changed, 11 insertions, 0 deletions

diff --git a/kernel/power/process.c b/kernel/power/process.c
index fc0df8486449..06ec8869dbf1 100644
--- a/kernel/power/process.c
+++ b/kernel/power/process.c
@@ -109,6 +109,8 @@ static int try_to_freeze_tasks(bool user_only)
 
 /**
  * freeze_processes - Signal user space processes to enter the refrigerator.
+ * The current thread will not be frozen.  The same process that calls
+ * freeze_processes must later call thaw_processes.
  *
  * On success, returns 0.  On failure, -errno and system is fully thawed.
  */
@@ -120,6 +122,9 @@ int freeze_processes(void)
         if (error)
                 return error;
 
+        /* Make sure this task doesn't get frozen */
+        current->flags |= PF_SUSPEND_TASK;
+
         if (!pm_freezing)
                 atomic_inc(&system_freezing_cnt);
 
@@ -168,6 +173,7 @@ int freeze_kernel_threads(void)
 void thaw_processes(void)
 {
         struct task_struct *g, *p;
+        struct task_struct *curr = current;
 
         if (pm_freezing)
                 atomic_dec(&system_freezing_cnt);
@@ -182,10 +188,15 @@ void thaw_processes(void)
 
         read_lock(&tasklist_lock);
         do_each_thread(g, p) {
+                /* No other threads should have PF_SUSPEND_TASK set */
+                WARN_ON((p != curr) && (p->flags & PF_SUSPEND_TASK));
                 __thaw_task(p);
         } while_each_thread(g, p);
         read_unlock(&tasklist_lock);
 
+        WARN_ON(!(curr->flags & PF_SUSPEND_TASK));
+        curr->flags &= ~PF_SUSPEND_TASK;
+
         usermodehelper_enable();
 
         schedule();