kernel/linux.git/tools/testing/selftests/mm/uffd-unit-tests.c, branch v6.7

selftests/mm: add uffd unit test for UFFDIO_POISON

2023-08-18T17:12:18+00:00

The test is pretty basic, and exercises UFFDIO_POISON straightforwardly. We register a region with userfaultfd, in missing fault mode. For each fault, we either UFFDIO_COPY a zeroed page (odd pages) or UFFDIO_POISON (even pages). We do this mix to test "something like a real use case", where guest memory would be some mix of poisoned and non-poisoned pages. We read each page in the region, and assert that the odd pages are zeroed as expected, and the even pages yield a SIGBUS as expected. Why UFFDIO_COPY instead of UFFDIO_ZEROPAGE? Because hugetlb doesn't support UFFDIO_ZEROPAGE, and we don't want to have special case code. Link: https://lkml.kernel.org/r/20230707215540.2324998-9-axelrasmussen@google.com Signed-off-by: Axel Rasmussen Acked-by: Peter Xu Cc: Al Viro Cc: Brian Geffon Cc: Christian Brauner Cc: David Hildenbrand Cc: Gaosheng Cui Cc: Huang, Ying Cc: Hugh Dickins Cc: James Houghton Cc: Jan Alexander Steffens (heftig) Cc: Jiaqi Yan Cc: Jonathan Corbet Cc: Kefeng Wang Cc: Liam R. Howlett Cc: Miaohe Lin Cc: Mike Kravetz Cc: Mike Rapoport (IBM) Cc: Muchun Song Cc: Nadav Amit Cc: Naoya Horiguchi Cc: Ryan Roberts Cc: Shuah Khan Cc: Suleiman Souhlal Cc: Suren Baghdasaryan Cc: T.J. Alumbaugh Cc: Yu Zhao Cc: ZhangPeng Signed-off-by: Andrew Morton

selftests/mm: fix two -Wformat-security warnings in uffd builds

2023-06-19T23:19:02+00:00

The uffd tests generate two compile time warnings from clang's -Wformat-security setting. These trigger at the call sites for uffd_test_start() and uffd_test_skip(). 1) Fix the uffd_test_start() issue by removing the intermediate test_name variable (thanks to David Hildenbrand for showing how to do this). 2) Fix the uffd_test_skip() issue by observing that there is no need for a macro and a variable args approach, because all callers of uffd_test_skip() pass in a simple char* string, without any format specifiers. So just change uffd_test_skip() into a regular C function. Link: https://lkml.kernel.org/r/20230606071637.267103-7-jhubbard@nvidia.com Signed-off-by: John Hubbard Reviewed-by: David Hildenbrand Reviewed-by: Peter Xu Tested-by: Muhammad Usama Anjum Cc: Jonathan Corbet Cc: Nathan Chancellor Cc: Shuah Khan Signed-off-by: Andrew Morton

selftests/mm: add tests for RO pinning vs fork()

2023-04-21T21:52:00+00:00

Add a test suite (with 10 more sub-tests) to cover RO pinning against fork() over uffd-wp. It covers both: (1) Early CoW test in fork() when page pinned, (2) page unshare due to RO longterm pin. They are: Testing wp-fork-pin on anon... done Testing wp-fork-pin on shmem... done Testing wp-fork-pin on shmem-private... done Testing wp-fork-pin on hugetlb... done Testing wp-fork-pin on hugetlb-private... done Testing wp-fork-pin-with-event on anon... done Testing wp-fork-pin-with-event on shmem... done Testing wp-fork-pin-with-event on shmem-private... done Testing wp-fork-pin-with-event on hugetlb... done Testing wp-fork-pin-with-event on hugetlb-private... done CONFIG_GUP_TEST needed or they'll be skipped. Testing wp-fork-pin on anon... skipped [reason: Possibly CONFIG_GUP_TEST missing or unprivileged] Note that the major test goal is on private memory, but no hurt to also run all of them over shared because shared memory should work the same. Link: https://lkml.kernel.org/r/20230417195317.898696-7-peterx@redhat.com Signed-off-by: Peter Xu Cc: Andrea Arcangeli Cc: Axel Rasmussen Cc: David Hildenbrand Cc: Mika Penttilä Cc: Mike Kravetz Cc: Nadav Amit Signed-off-by: Andrew Morton

selftests/mm: extend and rename uffd pagemap test

2023-04-21T21:52:00+00:00

Extend it to all types of mem, meanwhile add one parallel test when EVENT_FORK is enabled, where uffd-wp bits should be persisted rather than dropped. Since at it, rename the test to "wp-fork" to better show what it means. Making the new test called "wp-fork-with-event". Before: Testing pagemap on anon... done After: Testing wp-fork on anon... done Testing wp-fork on shmem... done Testing wp-fork on shmem-private... done Testing wp-fork on hugetlb... done Testing wp-fork on hugetlb-private... done Testing wp-fork-with-event on anon... done Testing wp-fork-with-event on shmem... done Testing wp-fork-with-event on shmem-private... done Testing wp-fork-with-event on hugetlb... done Testing wp-fork-with-event on hugetlb-private... done Link: https://lkml.kernel.org/r/20230417195317.898696-5-peterx@redhat.com Signed-off-by: Peter Xu Cc: Andrea Arcangeli Cc: Axel Rasmussen Cc: David Hildenbrand Cc: Mika Penttilä Cc: Mike Kravetz Cc: Nadav Amit Signed-off-by: Andrew Morton

selftests/mm: add a few options for uffd-unit-test

2023-04-21T21:52:00+00:00

Namely: "-f": add a wildcard filter for tests to run "-l": list tests rather than running any "-h": help msg Link: https://lkml.kernel.org/r/20230417195317.898696-4-peterx@redhat.com Signed-off-by: Peter Xu Reviewed-by: David Hildenbrand Cc: Andrea Arcangeli Cc: Axel Rasmussen Cc: Mika Penttilä Cc: Mike Kravetz Cc: Nadav Amit Signed-off-by: Andrew Morton

selftests/mm: add uffdio register ioctls test

2023-04-18T23:30:08+00:00

This new test tests against the returned ioctls from UFFDIO_REGISTER, where put into uffdio_register.ioctls. This also tests the expected failure cases of UFFDIO_REGISTER, aka: - Register with empty mode should fail with -EINVAL - Register minor without page cache (anon) should fail with -EINVAL Link: https://lkml.kernel.org/r/20230412164548.329376-1-peterx@redhat.com Signed-off-by: Peter Xu Cc: Axel Rasmussen Cc: David Hildenbrand Cc: Dmitry Safonov <0x7f454c46@gmail.com> Cc: Mike Kravetz Cc: Mike Rapoport (IBM) Cc: Zach O'Keefe Signed-off-by: Andrew Morton

selftests/mm: allow uffd test to skip properly with no privilege

2023-04-18T23:30:08+00:00

Allow skip a unit test properly due to no privilege (e.g. sigbus and events tests). [colin.i.king@gmail.com: fix spelling mistake "priviledge" -> "privilege"] Link: https://lkml.kernel.org/r/20230414081506.1678998-1-colin.i.king@gmail.com Link: https://lkml.kernel.org/r/20230412164520.329163-1-peterx@redhat.com Signed-off-by: Peter Xu Signed-off-by: Colin Ian King Cc: Axel Rasmussen Cc: David Hildenbrand Cc: Dmitry Safonov <0x7f454c46@gmail.com> Cc: Mike Kravetz Cc: Mike Rapoport (IBM) Cc: Zach O'Keefe Signed-off-by: Andrew Morton

selftests/mm: workaround no way to detect uffd-minor + wp

2023-04-18T23:30:07+00:00

Userfaultfd minor+wp mode was very recently added. The test will fail on the old kernels at ioctl(UFFDIO_CONTINUE) which is misterious. Unfortunately there's no feature bit to detect for this support. Add a hack to leverage WP_UNPOPULATED to detect whether that feature existed, since WP_UNPOPULATED was merged right after minor+wp. Link: https://lkml.kernel.org/r/20230412164517.329152-1-peterx@redhat.com Signed-off-by: Peter Xu Cc: Axel Rasmussen Cc: David Hildenbrand Cc: Dmitry Safonov <0x7f454c46@gmail.com> Cc: Mike Kravetz Cc: Mike Rapoport (IBM) Cc: Zach O'Keefe Signed-off-by: Andrew Morton

selftests/mm: move zeropage test into uffd unit tests

2023-04-18T23:30:07+00:00

Simplifies it a bit along the way, e.g., drop the never used offset field (which was always the 1st page so offset=0). Introduce uffd_register_with_ioctls() out of uffd_register() to detect uffdio_register.ioctls got returned. Check that automatically when testing UFFDIO_ZEROPAGE on different types of memory (and kernel). Link: https://lkml.kernel.org/r/20230412164404.328815-1-peterx@redhat.com Signed-off-by: Peter Xu Cc: Axel Rasmussen Cc: David Hildenbrand Cc: Dmitry Safonov <0x7f454c46@gmail.com> Cc: Mike Kravetz Cc: Mike Rapoport (IBM) Cc: Zach O'Keefe Signed-off-by: Andrew Morton

selftests/mm: move uffd sig/events tests into uffd unit tests

2023-04-18T23:30:07+00:00

Move the two tests into the unit test, and convert it into 20 standalone tests: - events test on all 5 mem types, with wp on/off - signal test on all 5 mem types, with wp on/off Testing sigbus on anon... done Testing sigbus on shmem... done Testing sigbus on shmem-private... done Testing sigbus on hugetlb... done Testing sigbus on hugetlb-private... done Testing sigbus-wp on anon... done Testing sigbus-wp on shmem... done Testing sigbus-wp on shmem-private... done Testing sigbus-wp on hugetlb... done Testing sigbus-wp on hugetlb-private... done Testing events on anon... done Testing events on shmem... done Testing events on shmem-private... done Testing events on hugetlb... done Testing events on hugetlb-private... done Testing events-wp on anon... done Testing events-wp on shmem... done Testing events-wp on shmem-private... done Testing events-wp on hugetlb... done Testing events-wp on hugetlb-private... done It'll also remove a lot of global references along the way, e.g. test_uffdio_wp will be replaced with the wp value passed over. Link: https://lkml.kernel.org/r/20230412164400.328798-1-peterx@redhat.com Signed-off-by: Peter Xu Cc: Axel Rasmussen Cc: David Hildenbrand Cc: Dmitry Safonov <0x7f454c46@gmail.com> Cc: Mike Kravetz Cc: Mike Rapoport (IBM) Cc: Zach O'Keefe Signed-off-by: Andrew Morton