diff --git a/fs/ramfs/file-nommu.c b/fs/ramfs/file-nommu.c
index cad2b7a..237fe8b 100644
--- a/fs/ramfs/file-nommu.c
+++ b/fs/ramfs/file-nommu.c
@@ -295,5 +295,10 @@
  */
 int ramfs_nommu_mmap(struct file *file, struct vm_area_struct *vma)
 {
-	return vma->vm_flags & VM_SHARED ? 0 : -ENOSYS;
+	if (!(vma->vm_flags & VM_SHARED))
+		return -ENOSYS;
+
+	file_accessed(file);
+	vma->vm_ops = &generic_file_vm_ops;
+	return 0;
 }
diff --git a/ipc/shm.c b/ipc/shm.c
index d0259e3..d88ac5a 100644
--- a/ipc/shm.c
+++ b/ipc/shm.c
@@ -268,7 +268,9 @@
 	if (ret != 0)
 		return ret;
 	sfd->vm_ops = vma->vm_ops;
+#ifdef CONFIG_MMU
 	BUG_ON(!sfd->vm_ops->fault);
+#endif
 	vma->vm_ops = &shm_vm_ops;
 	shm_open(vma);