diff --git a/include/asm-x86_64/timex.h b/include/asm-x86_64/timex.h
index 8c6808a..f6527e1 100644
--- a/include/asm-x86_64/timex.h
+++ b/include/asm-x86_64/timex.h
@@ -27,6 +27,6 @@
 #define NS_SCALE        10 /* 2^10, carefully chosen */
 #define US_SCALE        32 /* 2^32, arbitralrily chosen */
 
-extern void mark_tsc_unstable(void);
+extern void mark_tsc_unstable(char *msg);
 extern void set_cyc2ns_scale(unsigned long khz);
 #endif