Merge tag 'irq-urgent-2020-03-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull irq fix from Thomas Gleixner:
 "A single bugfix to prevent reference leaks in irq affinity notifiers"

* tag 'irq-urgent-2020-03-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  genirq: Fix reference leaks on irq affinity notifiers

Author: torvalds

kernel/irq/manage.c

@@ -323,7 +323,11 @@ int irq_set_affinity_locked(struct irq_data *data, const struct cpumask *mask,
 
 	if (desc->affinity_notify) {
 		kref_get(&desc->affinity_notify->kref);
-		schedule_work(&desc->affinity_notify->work);
+		if (!schedule_work(&desc->affinity_notify->work)) {
+			/* Work was already scheduled, drop our extra ref */
+			kref_put(&desc->affinity_notify->kref,
+				 desc->affinity_notify->release);
+		}
 	}
 	irqd_set(data, IRQD_AFFINITY_SET);
 
@@ -423,7 +427,10 @@ irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify *notify)
 	raw_spin_unlock_irqrestore(&desc->lock, flags);
 
 	if (old_notify) {
-		cancel_work_sync(&old_notify->work);
+		if (cancel_work_sync(&old_notify->work)) {
+			/* Pending work had a ref, put that one too */
+			kref_put(&old_notify->kref, old_notify->release);
+		}
 		kref_put(&old_notify->kref, old_notify->release);
 	}