Doesn't seem worth maintaining a FIXME for this.
---
 drivers/md/dm-thin.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Index: linux-3.1-rc9/drivers/md/dm-thin.c
===================================================================
--- linux-3.1-rc9.orig/drivers/md/dm-thin.c
+++ linux-3.1-rc9/drivers/md/dm-thin.c
@@ -820,7 +820,7 @@ static void process_prepared_mapping(str
 	} else
 		cell_defer(tc, m->cell, m->data_block);
 
-	list_del(&m->list);	/* FIXME: unnecc.? */
+	list_del(&m->list);
 	mempool_free(m, tc->pool->mapping_pool);
 }