On Sat, Feb 26, 2022 at 06:25:15PM -0800, Hugh Dickins wrote: > - if (!folio_test_ksm(folio)) > + /* Skip call in common case, plus .pgoff is invalid for KSM */ > + if (pvmw.nr_pages != 1 && !folio_test_hugetlb(folio)) > idx = linear_page_index(vma, pvmw.address) - pvmw.pgoff; How do you feel about this instead? - if (!folio_test_ksm(folio)) + /* pgoff is invalid for ksm pages, but they are never large */ + if (folio_test_large(folio) && !folio_test_hugetlb(folio)) idx = linear_page_index(vma, pvmw.address) - pvmw.pgoff;