diff --git a/include/linux/mm.h b/include/linux/mm.h
index bf16a79e6c11..1efc75b9200f 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -649,6 +649,13 @@ static inline void vm_flags_reset(struct vm_area_struct *vma,
 	vm_flags_init(vma, flags);
 }
 
+static inline void vm_flags_reset_once(struct vm_area_struct *vma,
+				       vm_flags_t flags)
+{
+	mmap_assert_write_locked(vma->vm_mm);
+	WRITE_ONCE(ACCESS_PRIVATE(vma, __vm_flags), flags);
+}
+
 static inline void vm_flags_set(struct vm_area_struct *vma,
 				vm_flags_t flags)
 {
diff --git a/mm/mlock.c b/mm/mlock.c
index c17984cb14d1..9738d49bbc24 100644
--- a/mm/mlock.c
+++ b/mm/mlock.c
@@ -380,7 +380,7 @@ static void mlock_vma_pages_range(struct vm_area_struct *vma,
 	 */
 	if (newflags & VM_LOCKED)
 		newflags |= VM_IO;
-	vm_flags_reset(vma, newflags);
+	vm_flags_reset_once(vma, newflags);
 
 	lru_add_drain();
 	walk_page_range(vma->vm_mm, start, end, &mlock_walk_ops, NULL);
@@ -388,7 +388,7 @@ static void mlock_vma_pages_range(struct vm_area_struct *vma,
 
 	if (newflags & VM_IO) {
 		newflags &= ~VM_IO;
-		vm_flags_reset(vma, newflags);
+		vm_flags_reset_once(vma, newflags);
 	}
 }