--- a/mm/rmap.c~mm-rmap-fix-obsolete-comment-in-__page_check_anon_rmap +++ a/mm/rmap.c @@ -1086,8 +1086,7 @@ static void __page_check_anon_rmap(struc * be set up correctly at this point. * * We have exclusion against page_add_anon_rmap because the caller - * always holds the page locked, except if called from page_dup_rmap, - * in which case the page is already known to be setup. + * always holds the page locked. * * We have exclusion against page_add_new_anon_rmap because those pages * are initially only visible via the pagetables, and the pte is locked