This series is based on (mostly) v5.12-rc8-mmots-2021-04-21-23-08. It tries to fix some corner case bugs for uffd-wp on either thp or fork(). Then it introduced a new test with pagemap/pageout. Patch layout: Patch 1: cleanup for THP, it'll slightly simplify the follow up patches Patch 2-4: misc fixes for uffd-wp here and there; please refer to each patch Patch 5: add pagemap support for uffd-wp Patch 6: add pagemap/pageout test for uffd-wp The last test introduced can also verify some of the fixes in previous patches, as the test will fail without the fixes. However it's not easy to verify all the changes in patch 2-4, but hopefully they can still be properly reviewed. Note that if considering the ongoing uffd-wp shmem & hugetlbfs work, patch 5 will be incomplete as it's missing e.g. hugetlbfs part or the special swap pte detection. However that's not needed in this series, and since that series is still during review, this series does not depend on that one (the last test only runs with anonymous memory, not file-backed). So this series can be merged even before that series. Please review, thanks. Peter Xu (6): mm/thp: Simplify copying of huge zero page pmd when fork mm/userfaultfd: Fix uffd-wp special cases for fork() mm/userfaultfd: Fix a few thp pmd missing uffd-wp bit mm/userfaultfd: Fail uffd-wp registeration if not supported mm/pagemap: Export uffd-wp protection information userfaultfd/selftests: Add pagemap uffd-wp test Documentation/admin-guide/mm/pagemap.rst | 2 + fs/proc/task_mmu.c | 9 ++ fs/userfaultfd.c | 9 +- include/linux/huge_mm.h | 2 +- include/linux/swapops.h | 2 + mm/huge_memory.c | 36 +++--- mm/memory.c | 25 ++-- tools/testing/selftests/vm/userfaultfd.c | 154 +++++++++++++++++++++++ 8 files changed, 206 insertions(+), 33 deletions(-) -- 2.26.2
