diff --git a/ntoskrnl/include/internal/mm.h b/ntoskrnl/include/internal/mm.h
index a3a382cbcfc..81c3954d8ae 100644
--- a/ntoskrnl/include/internal/mm.h
+++ b/ntoskrnl/include/internal/mm.h
@@ -1434,7 +1434,7 @@ MmFlushSegment(
     _In_ PSECTION_OBJECT_POINTERS SectionObjectPointer,
     _In_opt_ PLARGE_INTEGER Offset,
     _In_ ULONG Length,
-    _In_opt_ PIO_STATUS_BLOCK Iosb);
+    _Out_opt_ PIO_STATUS_BLOCK Iosb);
 
 NTSTATUS
 NTAPI
diff --git a/ntoskrnl/mm/section.c b/ntoskrnl/mm/section.c
index c6b618cdbf8..b6a6ca67b4c 100644
--- a/ntoskrnl/mm/section.c
+++ b/ntoskrnl/mm/section.c
@@ -4663,7 +4663,7 @@ MmFlushSegment(
     _In_ PSECTION_OBJECT_POINTERS SectionObjectPointer,
     _In_opt_ PLARGE_INTEGER Offset,
     _In_ ULONG Length,
-    _In_opt_ PIO_STATUS_BLOCK Iosb)
+    _Out_opt_ PIO_STATUS_BLOCK Iosb)
 {
     LARGE_INTEGER FlushStart, FlushEnd;
     NTSTATUS Status;