Mark timer as running in the timer base _before_ we clear the pending

flag (and order it on SMP), so that del_timer_sync() always sees the
timer either pending or running if it is active.

diff --git a/kernel/timer.c b/kernel/timer.c
index 176d2c3215b4e8261dc03bc44449ba898047088d..1c513bd0b1e0e2d4b29deea4a66fd3b18f356d44 100644 (file)
--- a/kernel/timer.c
+++ b/kernel/timer.c
@@ -418,8 +418,9 @@ repeat:
                        data = timer->data;
 
                        list_del(&timer->entry);
-                       timer->base = NULL;
                        set_running_timer(base, timer);
+                       smp_wmb();
+                       timer->base = NULL;
                        spin_unlock_irq(&base->lock);
                        fn(data);
                        spin_lock_irq(&base->lock);