diff --git a/todo b/todo
index 6b6f93b..3ea4e30 100644
--- a/todo
+++ b/todo
@@ -2,5 +2,6 @@
   using shared_ptr.
 * Ensure that we comb through the current code and enforce the distinction
   between user errors and program exceptions.
-* Investigate using MONITOR/MWAIT for spinlocks to reduce busy-waiting
+* Investigate using UMONITOR/UMWAIT for spinlocks to reduce busy-waiting
   stress/power consumption. Look for a parallel on ARM.
+* Investigate WFE/SEV to reduce busy-waiting in spinlocks on ARM.