2 files changed, 5 insertions, 0 deletions

diff --git a/include/linux/irq.h b/include/linux/irq.h
index af7052c6a45c..298a9b9ce675 100644
--- a/include/linux/irq.h
+++ b/include/linux/irq.h
@@ -679,6 +679,7 @@ struct irq_chip_type {
  * @num_ct:             Number of available irq_chip_type instances (usually 1)
  * @private:            Private data for non generic chip callbacks
  * @installed:          bitfield to denote installed interrupts
+ * @unused:             bitfield to denote unused interrupts
  * @domain:             irq domain pointer
  * @list:               List head for keeping track of instances
  * @chip_types:         Array of interrupt irq_chip_types
@@ -702,6 +703,7 @@ struct irq_chip_generic {
         unsigned int            num_ct;
         void                    *private;
         unsigned long           installed;
+        unsigned long           unused;
         struct irq_domain       *domain;
         struct list_head        list;
         struct irq_chip_type    chip_types[0];
diff --git a/kernel/irq/generic-chip.c b/kernel/irq/generic-chip.c
index 8743d62fded7..95575d8d5392 100644
--- a/kernel/irq/generic-chip.c
+++ b/kernel/irq/generic-chip.c
@@ -359,6 +359,9 @@ static int irq_map_generic_chip(struct irq_domain *d, unsigned int virq,
 
         idx = hw_irq % dgc->irqs_per_chip;
 
+        if (test_bit(idx, &gc->unused))
+                return -ENOTSUPP;
+
         if (test_bit(idx, &gc->installed))
                 return -EBUSY;