Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland...

[linux-2.6] / kernel / hrtimer.c

diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c
index 421be5fe5cc78f5d2be0eabd3ba2367fe1b15b3e..ab80515008f4740fd980b1089d922811978ccff4 100644 (file)
--- a/kernel/hrtimer.c
+++ b/kernel/hrtimer.c
@@ -1003,10 +1003,18 @@ hrtimer_start(struct hrtimer *timer, ktime_t tim, const enum hrtimer_mode mode)
         */
        raise = timer->state == HRTIMER_STATE_PENDING;
 
+       /*
+        * We use preempt_disable to prevent this task from migrating after
+        * setting up the softirq and raising it. Otherwise, if me migrate
+        * we will raise the softirq on the wrong CPU.
+        */
+       preempt_disable();
+
        unlock_hrtimer_base(timer, &flags);
 
        if (raise)
                hrtimer_raise_softirq();
+       preempt_enable();
 
        return ret;
 }