diff --git a/arch/parisc/kernel/irq.c b/arch/parisc/kernel/irq.c
index e76c866199493..60f5829d476f5 100644
--- a/arch/parisc/kernel/irq.c
+++ b/arch/parisc/kernel/irq.c
@@ -376,7 +376,11 @@ static inline int eirr_to_irq(unsigned long eirr)
 /*
  * IRQ STACK - used for irq handler
  */
+#ifdef CONFIG_64BIT
+#define IRQ_STACK_SIZE      (4096 << 4) /* 64k irq stack size */
+#else
 #define IRQ_STACK_SIZE      (4096 << 3) /* 32k irq stack size */
+#endif
 
 union irq_stack_union {
 	unsigned long stack[IRQ_STACK_SIZE/sizeof(unsigned long)];