The patch titled Subject: thp: decrement refcount on huge zero page if it is split has been added to the -mm tree. Its filename is thp-decrement-refcount-on-huge-zero-page-if-it-is-split.patch This patch should soon appear at http://ozlabs.org/~akpm/mmots/broken-out/thp-decrement-refcount-on-huge-zero-page-if-it-is-split.patch and later at http://ozlabs.org/~akpm/mmotm/broken-out/thp-decrement-refcount-on-huge-zero-page-if-it-is-split.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: "Kirill A. Shutemov" <kirill.shutemov@xxxxxxxxxxxxxxx> Subject: thp: decrement refcount on huge zero page if it is split The DAX code neglected to put the refcount on the huge zero page. Also we must notify on splits. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx> Signed-off-by: Matthew Wilcox <willy@xxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/huge_memory.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff -puN mm/huge_memory.c~thp-decrement-refcount-on-huge-zero-page-if-it-is-split mm/huge_memory.c --- a/mm/huge_memory.c~thp-decrement-refcount-on-huge-zero-page-if-it-is-split +++ a/mm/huge_memory.c @@ -2983,7 +2983,9 @@ again: if (unlikely(!pmd_trans_huge(*pmd))) goto unlock; if (vma_is_dax(vma)) { - pmdp_huge_clear_flush(vma, haddr, pmd); + pmd_t _pmd = pmdp_huge_clear_flush_notify(vma, haddr, pmd); + if (is_huge_zero_pmd(_pmd)) + put_huge_zero_page(); } else if (is_huge_zero_pmd(*pmd)) { __split_huge_zero_page_pmd(vma, haddr, pmd); } else { _ Patches currently in -mm which might be from kirill.shutemov@xxxxxxxxxxxxxxx are user_ns-use-correct-check-for-single-threadedness.patch mm-mlock-refactor-mlock-munlock-and-munlockall-code.patch mm-mlock-add-new-mlock-system-call.patch mm-introduce-vm_lockonfault.patch mm-mlock-add-mlock-flags-to-enable-vm_lockonfault-usage.patch selftests-vm-add-tests-for-lock-on-fault.patch mips-add-entry-for-new-mlock2-syscall.patch mm-fix-status-code-move_pages-returns-for-zero-page.patch mm-make-gup-handle-pfn-mapping-unless-foll_get-is-requested.patch mm-make-gup-handle-pfn-mapping-unless-foll_get-is-requested-fix.patch mremap-dont-leak-new_vma-if-f_op-mremap-fails.patch mm-move-mremap-from-file_operations-to-vm_operations_struct.patch mremap-dont-do-mm_populatenew_addr-on-failure.patch mremap-dont-do-uneccesary-checks-if-new_len-==-old_len.patch mremap-simplify-the-overlap-check-in-mremap_to.patch mm-introduce-vma_is_anonymousvma-helper.patch mmap-fix-the-usage-of-vm_pgoff-in-special_mapping-paths.patch mremap-fix-the-wrong-vma-vm_file-check-in-copy_vma.patch thp-vma_adjust_trans_huge-adjust-file-backed-vma-too.patch dax-move-dax-related-functions-to-a-new-header.patch thp-prepare-for-dax-huge-pages.patch mm-add-a-pmd_fault-handler.patch mm-export-various-functions-for-the-benefit-of-dax.patch mm-add-vmf_insert_pfn_pmd.patch dax-add-huge-page-fault-support.patch ext2-huge-page-fault-support.patch ext4-huge-page-fault-support.patch xfs-huge-page-fault-support.patch thp-decrement-refcount-on-huge-zero-page-if-it-is-split.patch thp-fix-zap_huge_pmd-for-dax.patch dax-dont-use-set_huge_zero_page.patch dax-ensure-that-zero-pages-are-removed-from-other-processes.patch mm-page_isolation-remove-bogus-tests-for-isolated-pages.patch mm-rename-and-move-get-set_freepage_migratetype.patch mempolicy-get-rid-of-duplicated-check-for-vmavm_pfnmap-in-queue_pages_range.patch vm_flags-vm_flags_t-and-__nocast.patch page-flags-trivial-cleanup-for-pagetrans-helpers.patch page-flags-introduce-page-flags-policies-wrt-compound-pages.patch page-flags-define-pg_locked-behavior-on-compound-pages.patch page-flags-define-behavior-of-fs-io-related-flags-on-compound-pages.patch page-flags-define-behavior-of-lru-related-flags-on-compound-pages.patch page-flags-define-behavior-of-lru-related-flags-on-compound-pages-fix.patch page-flags-define-behavior-slb-related-flags-on-compound-pages.patch page-flags-define-behavior-of-xen-related-flags-on-compound-pages.patch page-flags-define-pg_reserved-behavior-on-compound-pages.patch page-flags-define-pg_swapbacked-behavior-on-compound-pages.patch page-flags-define-pg_swapcache-behavior-on-compound-pages.patch page-flags-define-pg_mlocked-behavior-on-compound-pages.patch page-flags-define-pg_uncached-behavior-on-compound-pages.patch page-flags-define-pg_uptodate-behavior-on-compound-pages.patch page-flags-look-on-head-page-if-the-flag-is-encoded-in-page-mapping.patch mm-sanitize-page-mapping-for-tail-pages.patch include-linux-page-flagsh-rename-macros-to-avoid-collisions.patch fix-list_poison12-offset.patch use-poison_pointer_delta-for-poison-pointers.patch remove-not-used-poison-pointer-macros.patch mm-mark-most-vm_operations_struct-const.patch mm-mpx-add-vm_flags_t-vm_flags-arg-to-do_mmap_pgoff.patch mm-make-sure-all-file-vmas-have-vm_ops-set.patch mm-use-vma_is_anonymous-in-create_huge_pmd-and-wp_huge_pmd.patch mm-madvise-use-vma_is_anonymous-to-check-for-anon-vma.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html