diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index dd66c6ad5af1..009eb3adc2b7 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -3762,6 +3762,10 @@ static void __split_folio_to_order(struct folio *folio, int old_order,
 		 */
 		VM_WARN_ON_ONCE_PAGE(new_folio->private, new_head);
 
+		/*
+		 * Not all folio fields are valid during a split, so open-code
+		 * the swap entry rather than using folio_swap_entry().
+		 */
 		if (folio_test_swapcache(folio))
 			new_folio->swap.val = folio->swap.val + i;