2 files changed, 15 insertions, 3 deletions

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index a02b624fee6c..71b836034912 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -333,9 +333,12 @@ static inline struct rq *__task_rq_lock(struct task_struct *p)
         for (;;) {
                 rq = task_rq(p);
                 raw_spin_lock(&rq->lock);
-                if (likely(rq == task_rq(p)))
+                if (likely(rq == task_rq(p) && !task_on_rq_migrating(p)))
                         return rq;
                 raw_spin_unlock(&rq->lock);
+
+                while (unlikely(task_on_rq_migrating(p)))
+                        cpu_relax();
         }
 }
 
@@ -352,10 +355,13 @@ static struct rq *task_rq_lock(struct task_struct *p, unsigned long *flags)
                 raw_spin_lock_irqsave(&p->pi_lock, *flags);
                 rq = task_rq(p);
                 raw_spin_lock(&rq->lock);
-                if (likely(rq == task_rq(p)))
+                if (likely(rq == task_rq(p) && !task_on_rq_migrating(p)))
                         return rq;
                 raw_spin_unlock(&rq->lock);
                 raw_spin_unlock_irqrestore(&p->pi_lock, *flags);
+
+                while (unlikely(task_on_rq_migrating(p)))
+                        cpu_relax();
         }
 }
 
@@ -1678,7 +1684,7 @@ try_to_wake_up(struct task_struct *p, unsigned int state, int wake_flags)
         success = 1; /* we're going to change ->state */
         cpu = task_cpu(p);
 
-        if (task_on_rq_queued(p) && ttwu_remote(p, wake_flags))
+        if (p->on_rq && ttwu_remote(p, wake_flags))
                 goto stat;
 
 #ifdef CONFIG_SMP
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index 26566d0c67ac..aa0f73ba3777 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -17,6 +17,7 @@ struct rq;
 
 /* task_struct::on_rq states: */
 #define TASK_ON_RQ_QUEUED       1
+#define TASK_ON_RQ_MIGRATING    2
 
 extern __read_mostly int scheduler_running;
 
@@ -950,6 +951,11 @@ static inline int task_on_rq_queued(struct task_struct *p)
         return p->on_rq == TASK_ON_RQ_QUEUED;
 }
 
+static inline int task_on_rq_migrating(struct task_struct *p)
+{
+        return p->on_rq == TASK_ON_RQ_MIGRATING;
+}
+
 #ifndef prepare_arch_switch
 # define prepare_arch_switch(next)      do { } while (0)
 #endif