diff --git a/arch/ia64/Kconfig b/arch/ia64/Kconfig
index 3d31636..6183aec 100644
--- a/arch/ia64/Kconfig
+++ b/arch/ia64/Kconfig
@@ -17,6 +17,7 @@
 	select ACPI if (!IA64_HP_SIM)
 	select PM if (!IA64_HP_SIM)
 	select ARCH_SUPPORTS_MSI
+	select HAVE_UNSTABLE_SCHED_CLOCK
 	select HAVE_IDE
 	select HAVE_OPROFILE
 	select HAVE_KPROBES