1 files changed, 26 insertions, 45 deletions

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 7880f4f64d0e..44123b4d14e8 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -1065,7 +1065,7 @@ uclamp_update_active(struct task_struct *p, enum uclamp_id clamp_id)
 	 * affecting a valid clamp bucket, the next time it's enqueued,
 	 * it will already see the updated clamp bucket value.
 	 */
-	if (!p->uclamp[clamp_id].active) {
+	if (p->uclamp[clamp_id].active) {
 		uclamp_rq_dec_id(rq, p, clamp_id);
 		uclamp_rq_inc_id(rq, p, clamp_id);
 	}
@@ -1073,6 +1073,7 @@ uclamp_update_active(struct task_struct *p, enum uclamp_id clamp_id)
 	task_rq_unlock(rq, p, &rf);
 }
 
+#ifdef CONFIG_UCLAMP_TASK_GROUP
 static inline void
 uclamp_update_active_tasks(struct cgroup_subsys_state *css,
 			   unsigned int clamps)
@@ -1091,7 +1092,6 @@ uclamp_update_active_tasks(struct cgroup_subsys_state *css,
 	css_task_iter_end(&it);
 }
 
-#ifdef CONFIG_UCLAMP_TASK_GROUP
 static void cpu_util_update_eff(struct cgroup_subsys_state *css);
 static void uclamp_update_root_tg(void)
 {
@@ -3929,13 +3929,22 @@ pick_next_task(struct rq *rq, struct task_struct *prev, struct rq_flags *rf)
 	}
 
 restart:
+#ifdef CONFIG_SMP
 	/*
-	 * Ensure that we put DL/RT tasks before the pick loop, such that they
-	 * can PULL higher prio tasks when we lower the RQ 'priority'.
+	 * We must do the balancing pass before put_next_task(), such
+	 * that when we release the rq->lock the task is in the same
+	 * state as before we took rq->lock.
+	 *
+	 * We can terminate the balance pass as soon as we know there is
+	 * a runnable task of @class priority or higher.
 	 */
-	prev->sched_class->put_prev_task(rq, prev, rf);
-	if (!rq->nr_running)
-		newidle_balance(rq, rf);
+	for_class_range(class, prev->sched_class, &idle_sched_class) {
+		if (class->balance(rq, prev, rf))
+			break;
+	}
+#endif
+
+	put_prev_task(rq, prev);
 
 	for_each_class(class) {
 		p = class->pick_next_task(rq, NULL, NULL);
@@ -5106,9 +5115,6 @@ static int sched_copy_attr(struct sched_attr __user *uattr, struct sched_attr *a
 	u32 size;
 	int ret;
 
-	if (!access_ok(uattr, SCHED_ATTR_SIZE_VER0))
-		return -EFAULT;
-
 	/* Zero the full structure, so that a short copy will be nice: */
 	memset(attr, 0, sizeof(*attr));
 
@@ -5116,45 +5122,19 @@ static int sched_copy_attr(struct sched_attr __user *uattr, struct sched_attr *a
 	if (ret)
 		return ret;
 
-	/* Bail out on silly large: */
-	if (size > PAGE_SIZE)
-		goto err_size;
-
 	/* ABI compatibility quirk: */
 	if (!size)
 		size = SCHED_ATTR_SIZE_VER0;
-
-	if (size < SCHED_ATTR_SIZE_VER0)
+	if (size < SCHED_ATTR_SIZE_VER0 || size > PAGE_SIZE)
 		goto err_size;
 
-	/*
-	 * If we're handed a bigger struct than we know of,
-	 * ensure all the unknown bits are 0 - i.e. new
-	 * user-space does not rely on any kernel feature
-	 * extensions we dont know about yet.
-	 */
-	if (size > sizeof(*attr)) {
-		unsigned char __user *addr;
-		unsigned char __user *end;
-		unsigned char val;
-
-		addr = (void __user *)uattr + sizeof(*attr);
-		end  = (void __user *)uattr + size;
-
-		for (; addr < end; addr++) {
-			ret = get_user(val, addr);
-			if (ret)
-				return ret;
-			if (val)
-				goto err_size;
-		}
-		size = sizeof(*attr);
+	ret = copy_struct_from_user(attr, sizeof(*attr), uattr, size);
+	if (ret) {
+		if (ret == -E2BIG)
+			goto err_size;
+		return ret;
 	}
 
-	ret = copy_from_user(attr, uattr, size);
-	if (ret)
-		return -EFAULT;
-
 	if ((attr->sched_flags & SCHED_FLAG_UTIL_CLAMP) &&
 	    size < SCHED_ATTR_SIZE_VER1)
 		return -EINVAL;
@@ -5354,7 +5334,7 @@ sched_attr_copy_to_user(struct sched_attr __user *uattr,
  * sys_sched_getattr - similar to sched_getparam, but with sched_attr
  * @pid: the pid in question.
  * @uattr: structure containing the extended parameters.
- * @usize: sizeof(attr) that user-space knows about, for forwards and backwards compatibility.
+ * @usize: sizeof(attr) for fwd/bwd comp.
  * @flags: for future extension.
  */
 SYSCALL_DEFINE4(sched_getattr, pid_t, pid, struct sched_attr __user *, uattr,
@@ -6039,10 +6019,11 @@ void init_idle(struct task_struct *idle, int cpu)
 	struct rq *rq = cpu_rq(cpu);
 	unsigned long flags;
 
+	__sched_fork(0, idle);
+
 	raw_spin_lock_irqsave(&idle->pi_lock, flags);
 	raw_spin_lock(&rq->lock);
 
-	__sched_fork(0, idle);
 	idle->state = TASK_RUNNING;
 	idle->se.exec_start = sched_clock();
 	idle->flags |= PF_IDLE;
@@ -6230,7 +6211,7 @@ static struct task_struct *__pick_migrate_task(struct rq *rq)
 	for_each_class(class) {
 		next = class->pick_next_task(rq, NULL, NULL);
 		if (next) {
-			next->sched_class->put_prev_task(rq, next, NULL);
+			next->sched_class->put_prev_task(rq, next);
 			return next;
 		}
 	}