diff --git a/kernel/proc.h b/kernel/proc.h
index 8e90008..f6ca8b7 100644
--- a/kernel/proc.h
+++ b/kernel/proc.h
@@ -93,7 +93,7 @@ struct proc {
   int xstate;                  // Exit status to be returned to parent's wait
   int pid;                     // Process ID
 
-  // proc_tree_lock must be held when using this:
+  // wait_lock must be held when using this:
   struct proc *parent;         // Parent process
 
   // these are private to the process, so p->lock need not be held.