Hi Sayali,
I tested the full series, and overall it looks good. In particular, the series resolves the issue reported in v2 [1], and the other patches in the series behaved as expected during my testing. [1]: https://lore.kernel.org/all/[email protected]/ The only concern I observed is specific to patch 15/15. On systems using 1GB huge pages, I noticed below failure. ./test_hugetlb_memcg # Hugepage size: 1048576 kB # memory usage should go back down. # expected memory: 4194304 # actual memory: 8388608 not ok 1 test_hugetlb_memcg Apart from this case, the rest of the series tested cleanly for me. Based on that, it seems that dropping patch 15/15 independently makes sense. Hence for the series, Tested-by: Venkat Rao Bagalkote <[email protected]> Regards, Venkat > On 6 Apr 2026, at 2:49 PM, Sayali Patil <[email protected]> wrote: > > Hi all, > > Powerpc systems with a 64K base page size exposed several issues while > running mm selftests. Some tests assume specific hugetlb configurations, > use incorrect interfaces, or fail instead of skipping when the required > kernel features are not available. > > This series fixes these issues and improves test robustness. > > Please review the patches and provide any feedback or suggestions for > improvement. > > Thanks, > Sayali > > --- > v3->v4 > > - selftests/mm: restore default nr_hugepages value via EXIT > trap in charge_reserved_hugetlb.sh: > Updated to use an EXIT trap to restore the original nr_hugepages > once at script termination, ensuring reliable restoration on all > exit paths. > > - selftest/mm: fix cgroup task placement and drop memory.current checks > in hugetlb_reparenting_test.sh: > Updated to use a deterministic synchronization method by migrating the > workload process within a wrapper subshell before calling exec() to > ensure correct cgroup accounting. > > - selftest/mm: align memory size to huge page size in hugepage-mremap > test: > Update test code directly to align memory allocations to the hugepage > size, rather than modifying run_vmtests.sh. This replaces the previous > commit “adjust hugepage-mremap test size for large huge pages” with > a cleaner, direct approach in the test itself. > > - selftests/mm: ensure destination is hugetlb-backed in hugepage-mremap: > Updated to remove MAP_POPULATE flag for the mmap call as per review > comment. > > - selftests/mm: skip uffd-wp-mremap if UFFD write-protect is unsupported: > Updated as per review comment to initialize features to zero and exit > on all uffd_get_features() failures, avoiding spurious test errors. > > - selftests/mm: move hwpoison setup into run_test() and silence > modprobe output for memory-failure category: > Declared LOADED_MOD as local variable and avoided a redundant > skip message when the module is not found. > Updated logic to set exitcode to ksft_skip only when no failure has > been recorded. > > - selftests/cgroup: extend test_hugetlb_memcg.c to support all huge > page sizes: > Updated to skip on memory constraints instead of returning > EXIT_FAILURE. > Updated the logic to fully account for the scenario when the > per-CPU stock is empty and a refill charges MEMCG_CHARGE_BATCH. > Updated to avoid overflow on 32-bit systems for memory.max value. > > - Included "selftests/mm: restore default nr_hugepages value via > EXIT trap in hugetlb_reparenting_test.sh" > > - Included "selftests/mm: free dynamically allocated PMD-sized > buffers in split_huge_page_test" > > - Included "selftests/mm: clarify alternate unmapping in compaction_test" > > - Dropped "selftests/mm: fix double increment in linked list cleanup in > compaction_test": > The behaviour is intentional. > > v3: https://lore.kernel.org/all/[email protected]/ > > --- > v2->v3 > - selftests/mm: skip uffd-wp-mremap if UFFD write-protect is unsupported: > Rename function to check_uffd_wp_feature_supported() as suggested in > review. > - selftest/mm: fix cgroup task placement and drop memory.current checks > in hugetlb_reparenting_test.sh: > Drop memory.current validation from the hugetlb reparenting test. > Keep tolerance at 7MB (reverting earlier increase to 8MB in v1). > - Included "selftests/mm: allow PUD-level entries in compound testcase of hmm > tests" patch: > Extend the compound testcase checks to accept PUD-level mappings. > - Included "selftests/mm: replace hardcoded THP size with runtime PMD page > size in > hmm tests" patch: > Use read_pmd_pagesize() instead of TWOMEG and cap maximum THPs in > benchmarks to avoid integer overflow. > > v2: https://lore.kernel.org/all/[email protected]/ > > --- > v1->v2 > - For "selftests/mm: ensure destination is hugetlb-backed in > hugepage-mremap": > update FLAGS definition to MAP_HUGETLB | MAP_SHARED | MAP_POPULATE and > used it for mmap() calls as suggested during review. > > v1: https://lore.kernel.org/all/[email protected]/ > --- > > Sayali Patil (15): > selftests/mm: restore default nr_hugepages value via EXIT trap in > charge_reserved_hugetlb.sh > selftests/mm: fix hugetlb pathname construction in > charge_reserved_hugetlb.sh > selftests/mm: restore default nr_hugepages value via EXIT trap in > hugetlb_reparenting_test.sh > selftests/mm: fix hugetlb pathname construction in > hugetlb_reparenting_test.sh > selftests/mm: fix cgroup task placement and drop memory.current checks > in hugetlb_reparenting_test.sh > selftests/mm: size tmpfs according to PMD page size in > split_huge_page_test > selftests/mm: free dynamically allocated PMD-sized buffers in > split_huge_page_test > selftest/mm: align memory size to huge page size in hugepage-mremap > test > selftest/mm: register existing mapping with userfaultfd in > hugepage-mremap > selftests/mm: ensure destination is hugetlb-backed in hugepage-mremap > selftests/mm: skip uffd-wp-mremap if UFFD write-protect is unsupported > selftests/mm: skip uffd-stress test when nr_pages_per_cpu is zero > selftests/mm: move hwpoison setup into run_test() and silence modprobe > output for memory-failure category > selftests/mm: clarify alternate unmapping in compaction_test > selftests/cgroup: extend test_hugetlb_memcg.c to support all huge page > sizes > > .../selftests/cgroup/test_hugetlb_memcg.c | 90 ++++++++++++++----- > .../selftests/mm/charge_reserved_hugetlb.sh | 45 ++++++---- > tools/testing/selftests/mm/compaction_test.c | 3 + > tools/testing/selftests/mm/hugepage-mremap.c | 42 ++++----- > .../selftests/mm/hugetlb_reparenting_test.sh | 59 ++++++------ > tools/testing/selftests/mm/run_vmtests.sh | 52 +++++++---- > .../selftests/mm/split_huge_page_test.c | 27 ++++-- > tools/testing/selftests/mm/uffd-stress.c | 6 +- > tools/testing/selftests/mm/uffd-wp-mremap.c | 13 +++ > 9 files changed, 220 insertions(+), 117 deletions(-) > > -- > 2.52.0 >
