Merge tag 'v4.19.50-rt22' into toradex_4.19.y-rt

Linux 4.19.50-rt22

1 files changed, 22 insertions, 14 deletions

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index eb5568933ac1..91a9b2556fb0 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -24,7 +24,7 @@
 
 DEFINE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues);
 
-#if defined(CONFIG_SCHED_DEBUG) && defined(HAVE_JUMP_LABEL)
+#if defined(CONFIG_SCHED_DEBUG) && defined(CONFIG_JUMP_LABEL)
 /*
  * Debugging: various feature bits
  *
@@ -111,11 +111,12 @@ struct rq *task_rq_lock(struct task_struct *p, struct rq_flags *rf)
 		 *					[L] ->on_rq
 		 *	RELEASE (rq->lock)
 		 *
-		 * If we observe the old CPU in task_rq_lock, the acquire of
+		 * If we observe the old CPU in task_rq_lock(), the acquire of
 		 * the old rq->lock will fully serialize against the stores.
 		 *
-		 * If we observe the new CPU in task_rq_lock, the acquire will
-		 * pair with the WMB to ensure we must then also see migrating.
+		 * If we observe the new CPU in task_rq_lock(), the address
+		 * dependency headed by '[L] rq = task_rq()' and the acquire
+		 * will pair with the WMB to ensure we then also see migrating.
 		 */
 		if (likely(rq == task_rq(p) && !task_on_rq_migrating(p))) {
 			rq_pin_lock(rq, rf);
@@ -139,9 +140,8 @@ static void update_rq_clock_task(struct rq *rq, s64 delta)
  * In theory, the compile should just see 0 here, and optimize out the call
  * to sched_rt_avg_update. But I don't trust it...
  */
-#if defined(CONFIG_IRQ_TIME_ACCOUNTING) || defined(CONFIG_PARAVIRT_TIME_ACCOUNTING)
-	s64 steal = 0, irq_delta = 0;
-#endif
+	s64 __maybe_unused steal = 0, irq_delta = 0;
+
 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
 	irq_delta = irq_time_read(cpu_of(rq)) - rq->prev_irq_time;
 
@@ -181,7 +181,7 @@ static void update_rq_clock_task(struct rq *rq, s64 delta)
 
 	rq->clock_task += delta;
 
-#ifdef HAVE_SCHED_AVG_IRQ
+#ifdef CONFIG_HAVE_SCHED_AVG_IRQ
 	if ((irq_delta + steal) && sched_feat(NONTASK_CAPACITY))
 		update_irq_load_avg(rq, irq_delta + steal);
 #endif
@@ -416,10 +416,11 @@ void __wake_q_add(struct wake_q_head *head, struct task_struct *task,
 	 * its already queued (either by us or someone else) and will get the
 	 * wakeup due to that.
 	 *
-	 * This cmpxchg() executes a full barrier, which pairs with the full
-	 * barrier executed by the wakeup in wake_up_q().
+	 * In order to ensure that a pending wakeup will observe our pending
+	 * state, even in the failed case, an explicit smp_mb() must be used.
 	 */
-	if (cmpxchg(&node->next, NULL, WAKE_Q_TAIL))
+	smp_mb__before_atomic();
+	if (cmpxchg_relaxed(&node->next, NULL, WAKE_Q_TAIL))
 		return;
 
 	get_task_struct(task);
@@ -975,7 +976,7 @@ static struct rq *move_queued_task(struct rq *rq, struct rq_flags *rf,
 {
 	lockdep_assert_held(&rq->lock);
 
-	p->on_rq = TASK_ON_RQ_MIGRATING;
+	WRITE_ONCE(p->on_rq, TASK_ON_RQ_MIGRATING);
 	dequeue_task(rq, p, DEQUEUE_NOCLOCK);
 	set_task_cpu(p, new_cpu);
 	rq_unlock(rq, rf);
@@ -6624,6 +6625,8 @@ static void cpu_cgroup_attach(struct cgroup_taskset *tset)
 static int cpu_shares_write_u64(struct cgroup_subsys_state *css,
 				struct cftype *cftype, u64 shareval)
 {
+	if (shareval > scale_load_down(ULONG_MAX))
+		shareval = MAX_SHARES;
 	return sched_group_set_shares(css_tg(css), scale_load(shareval));
 }
 
@@ -6726,8 +6729,10 @@ int tg_set_cfs_quota(struct task_group *tg, long cfs_quota_us)
 	period = ktime_to_ns(tg->cfs_bandwidth.period);
 	if (cfs_quota_us < 0)
 		quota = RUNTIME_INF;
-	else
+	else if ((u64)cfs_quota_us <= U64_MAX / NSEC_PER_USEC)
 		quota = (u64)cfs_quota_us * NSEC_PER_USEC;
+	else
+		return -EINVAL;
 
 	return tg_set_cfs_bandwidth(tg, period, quota);
 }
@@ -6749,6 +6754,9 @@ int tg_set_cfs_period(struct task_group *tg, long cfs_period_us)
 {
 	u64 quota, period;
 
+	if ((u64)cfs_period_us > U64_MAX / NSEC_PER_USEC)
+		return -EINVAL;
+
 	period = (u64)cfs_period_us * NSEC_PER_USEC;
 	quota = tg->cfs_bandwidth.quota;
 
@@ -7063,7 +7071,7 @@ static int __maybe_unused cpu_period_quota_parse(char *buf,
 {
 	char tok[21];	/* U64_MAX */
 
-	if (!sscanf(buf, "%s %llu", tok, periodp))
+	if (sscanf(buf, "%20s %llu", tok, periodp) < 1)
 		return -EINVAL;
 
 	*periodp *= NSEC_PER_USEC;