Re: [PATCH v2] mm/rmap: fix missing barrier between anon_vma init and vma->anon_vma publish

diff --git a/mm/rmap.c b/mm/rmap.c
index d1819fd69938..f3b21aaa34ee 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c

@@ -209,7 +209,11 @@ int __anon_vma_prepare(struct vm_area_struct *vma)
        /* page_table_lock to protect against threads */
        spin_lock(&mm->page_table_lock);
        if (likely(!vma->anon_vma)) {
-               vma->anon_vma = anon_vma;
+               /*
+                * Make anon_vma fields visible before anon_vma is published.
+                * Paired with an address dependency in reusable_anon_vma().
+                */
+               smp_store_release(&vma->anon_vma, anon_vma);