diff --git a/include/asm-x86/processor.h b/include/asm-x86/processor.h
index 93b6adc72ad1..a2fb5a436418 100644
--- a/include/asm-x86/processor.h
+++ b/include/asm-x86/processor.h
@@ -155,6 +155,8 @@ static inline int hlt_works(int cpu)
 
 extern void cpu_detect(struct cpuinfo_x86 *c);
 
+extern struct pt_regs *idle_regs(struct pt_regs *);
+
 extern void early_cpu_init(void);
 extern void identify_boot_cpu(void);
 extern void identify_secondary_cpu(struct cpuinfo_x86 *);