diff --git a/mm/ksm.c b/mm/ksm.c
index 49d48d1e0998..fe42c17490b8 100644
--- a/mm/ksm.c
+++ b/mm/ksm.c
@@ -1115,7 +1115,8 @@ static inline void folio_set_stable_node(struct folio *folio,
 					 struct ksm_stable_node *stable_node)
 {
 	VM_WARN_ON_FOLIO(folio_test_anon(folio) && PageAnonExclusive(&folio->page), folio);
-	folio->mapping = (void *)((unsigned long)stable_node | FOLIO_MAPPING_KSM);
+	WRITE_ONCE(folio->mapping,
+		   (void *)((unsigned long)stable_node | FOLIO_MAPPING_KSM));
 }
 
 #ifdef CONFIG_SYSFS
@@ -3316,7 +3317,7 @@ void folio_migrate_ksm(struct folio *newfolio, struct folio *folio)
 	stable_node = folio_stable_node(folio);
 	if (stable_node) {
 		VM_BUG_ON_FOLIO(stable_node->kpfn != folio_pfn(folio), folio);
-		stable_node->kpfn = folio_pfn(newfolio);
+		WRITE_ONCE(stable_node->kpfn, folio_pfn(newfolio));
 		/*
 		 * newfolio->mapping was set in advance; now we need smp_wmb()
 		 * to make sure that the new stable_node->kpfn is visible