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

Pull scheduler fixes from Ingo Molnar:
 "Two fixes: a stop-machine preemption fix and a SCHED_DEADLINE fix"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/deadline: Fix switched_from_dl() warning
  stop_machine: Disable preemption when waking two stopper threads

2 files changed, 15 insertions, 2 deletions

diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
index fbfc3f1d368a..10c7b51c0d1f 100644
--- a/kernel/sched/deadline.c
+++ b/kernel/sched/deadline.c
@@ -2290,8 +2290,17 @@ static void switched_from_dl(struct rq *rq, struct task_struct *p)
         if (task_on_rq_queued(p) && p->dl.dl_runtime)
                 task_non_contending(p);
 
-        if (!task_on_rq_queued(p))
+        if (!task_on_rq_queued(p)) {
+                /*
+                 * Inactive timer is armed. However, p is leaving DEADLINE and
+                 * might migrate away from this rq while continuing to run on
+                 * some other class. We need to remove its contribution from
+                 * this rq running_bw now, or sub_rq_bw (below) will complain.
+                 */
+                if (p->dl.dl_non_contending)
+                        sub_running_bw(&p->dl, &rq->dl);
                 sub_rq_bw(&p->dl, &rq->dl);
+        }
 
         /*
          * We cannot use inactive_task_timer() to invoke sub_running_bw()
diff --git a/kernel/stop_machine.c b/kernel/stop_machine.c
index f89014a2c238..1ff523dae6e2 100644
--- a/kernel/stop_machine.c
+++ b/kernel/stop_machine.c
@@ -270,7 +270,11 @@ unlock:
                 goto retry;
         }
 
-        wake_up_q(&wakeq);
+        if (!err) {
+                preempt_disable();
+                wake_up_q(&wakeq);
+                preempt_enable();
+        }
 
         return err;
 }