diff --git a/arch/x86/include/asm/irq.h b/arch/x86/include/asm/irq.h
index 107eb21..f38481b 100644
--- a/arch/x86/include/asm/irq.h
+++ b/arch/x86/include/asm/irq.h
@@ -36,6 +36,7 @@
 extern void fixup_irqs(void);
 #endif
 
+extern void (*generic_interrupt_extension)(void);
 extern void init_IRQ(void);
 extern void native_init_IRQ(void);
 extern bool handle_irq(unsigned irq, struct pt_regs *regs);