diff --git a/rmm/src/arch/emulate.rs b/rmm/src/arch/emulate.rs
index 4d84ca2bac..91fa24bfe7 100644
--- a/rmm/src/arch/emulate.rs
+++ b/rmm/src/arch/emulate.rs
@@ -285,8 +285,8 @@ impl<A: Arch> Machine<A> {
         }
     }
 
-    fn invalidate(&mut self, _address: VirtualAddress) {
-        unimplemented!("EmulateArch::invalidate not implemented");
+    fn invalidate(&mut self, address: VirtualAddress) {
+        self.map.remove(&address);
     }
 
     //TODO: cleanup
diff --git a/src/syscall/futex.rs b/src/syscall/futex.rs
index 9b2cb54704..65df18fcec 100644
--- a/src/syscall/futex.rs
+++ b/src/syscall/futex.rs
@@ -37,7 +37,6 @@ type FutexList = HashMap<PhysicalAddress, Vec<FutexEntry>>;
 pub struct FutexEntry {
     // Virtual address, required if synchronizing across the same address space, if the memory is
     // CoW.
-    // TODO: FUTEX_REQUEUE
     target_virtaddr: VirtualAddress,
     // Context to wake up, and compare address spaces.
     context_lock: Arc<ContextLock>,