diff --git a/arch/x86/include/asm/traps.h b/arch/x86/include/asm/traps.h
index 707adc6..3cf525e 100644
--- a/arch/x86/include/asm/traps.h
+++ b/arch/x86/include/asm/traps.h
@@ -1,6 +1,7 @@
 #ifndef _ASM_X86_TRAPS_H
 #define _ASM_X86_TRAPS_H
 
+#include <linux/context_tracking_state.h>
 #include <linux/kprobes.h>
 
 #include <asm/debugreg.h>
@@ -110,6 +111,9 @@
 asmlinkage void mce_threshold_interrupt(void);
 #endif
 
+extern enum ctx_state ist_enter(struct pt_regs *regs);
+extern void ist_exit(struct pt_regs *regs, enum ctx_state prev_state);
+
 /* Interrupts/Exceptions */
 enum {
 	X86_TRAP_DE = 0,	/*  0, Divide-by-zero */