diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index 0454bfa24353e75d19536c21ec95343eb7cf1555..cedafa008de5a1196ff08a4422623893876b98b3 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -516,6 +516,7 @@ static void halt_fast_timekeeper(struct timekeeper *tk)
 }
 
 #ifdef CONFIG_GENERIC_TIME_VSYSCALL_OLD
+#warning Please contact your maintainers, as GENERIC_TIME_VSYSCALL_OLD compatibity will disappear soon.
 
 static inline void update_vsyscall(struct timekeeper *tk)
 {