1 files changed, 10 insertions, 2 deletions

diff --git a/kernel/timer.c b/kernel/timer.c
index 67316cb6a777..6ec7e7e0db43 100644
--- a/kernel/timer.c
+++ b/kernel/timer.c
@@ -861,7 +861,13 @@ EXPORT_SYMBOL(mod_timer);
  *
  * mod_timer_pinned() is a way to update the expire field of an
  * active timer (if the timer is inactive it will be activated)
- * and not allow the timer to be migrated to a different CPU.
+ * and to ensure that the timer is scheduled on the current CPU.
+ *
+ * Note that this does not prevent the timer from being migrated
+ * when the current CPU goes offline.  If this is a problem for
+ * you, use CPU-hotplug notifiers to handle it correctly, for
+ * example, cancelling the timer when the corresponding CPU goes
+ * offline.
  *
  * mod_timer_pinned(timer, expires) is equivalent to:
  *
@@ -1102,7 +1108,9 @@ static void call_timer_fn(struct timer_list *timer, void (*fn)(unsigned long),
          * warnings as well as problems when looking into
          * timer->lockdep_map, make a copy and use that here.
          */
-        struct lockdep_map lockdep_map = timer->lockdep_map;
+        struct lockdep_map lockdep_map;
+
+        lockdep_copy_map(&lockdep_map, &timer->lockdep_map);
 #endif
         /*
          * Couple the lock chain with the lock chain at