kernel/linux.git/tools/testing/selftests/vm, branch v5.10.261

selftests/mm: allow PUD-level entries in compound testcase of hmm tests

2026-07-24T13:49:04+00:00

[ Upstream commit 224ed0e019b122d08580362abe57574a78f2b5fa ] Patch series "selftests/mm: assorted fixes for hmm-tests", v3. This series fixes a few issues in hmm-tests that show up when page-size and huge-page configuration differ from the hardcoded assumptions the tests were written for (PMD/THP sizing, default hugepage size, and related cases). It also includes a fix to exclusive_cow: the test ignored the return value of fork(), so both parent and child ran the same teardown path. This patch (of 3): The HMM compound testcase currently assumes only PMD-level mappings and fails on systems where default_hugepagesz=1G is set, because the region is then reported by the device at PUD level. Determine the mapping level (PMD or PUD) the device reports for the first page of the range and require every page to match that level exactly via ASSERT_EQ(). This accepts PUD-level mappings while preserving the expected/observed protection values printed on failure, and rejects a fragmented mapping that mixes PMD- and PUD-level entries within the same range (which a per-page OR check would have let pass). Link: https://lore.kernel.org/20260611034102.1030738-1-aboorvad@linux.ibm.com Link: https://lore.kernel.org/20260611034102.1030738-2-aboorvad@linux.ibm.com Fixes: e478425bec93 ("mm/hmm: add tests for hmm_pfn_to_map_order()") Signed-off-by: Sayali Patil Co-developed-by: Aboorva Devarajan Signed-off-by: Aboorva Devarajan Cc: Alex Sierra Cc: Alistair Popple Cc: Balbir Singh Cc: David Hildenbrand Cc: Jason Gunthorpe Cc: Leon Romanovsky Cc: Liam R. Howlett Cc: Lorenzo Stoakes Cc: Matthew Brost Cc: Matthew Wilcox (Oracle) Cc: Michal Hocko Cc: Mike Rapoport Cc: Ralph Campbell Cc: Shuah Khan Cc: Suren Baghdasaryan Cc: Vlastimil Babka Signed-off-by: Andrew Morton Signed-off-by: Sasha Levin

selftests/mm: clarify alternate unmapping in compaction_test

2026-07-24T13:49:04+00:00

[ Upstream commit 69ba1d76d93ab818245333cf400928477ba72053 ] Add a comment explaining that every other entry in the list is unmapped to intentionally create fragmentation with locked pages before invoking check_compaction(). Link: https://lore.kernel.org/da5e0a8d5152e54152c0d2f456aac2fac35af291.1779296493.git.sayalip@linux.ibm.com Fixes: bd67d5c15cc1 ("Test compaction of mlocked memory") Signed-off-by: Sayali Patil Tested-by: Venkat Rao Bagalkote Cc: David Hildenbrand (Arm) Cc: Dev Jain Cc: Liam Howlett Cc: Miaohe Lin Cc: Michal Hocko Cc: Oscar Salvador Cc: "Ritesh Harjani (IBM)" Cc: Shuah Khan Cc: Zi Yan Signed-off-by: Andrew Morton Signed-off-by: Sasha Levin

selftests/mm/charge_reserved_hugetlb: drop mount size for hugetlbfs

2026-03-04T12:20:18+00:00

[ Upstream commit 1aa1dd9cc595917882fb6db67725442956f79607 ] charge_reserved_hugetlb.sh mounts a hugetlbfs instance at /mnt/huge with a fixed size of 256M. On systems with large base hugepages (e.g. 512MB), this is smaller than a single hugepage, so the hugetlbfs mount ends up with zero capacity (often visible as size=0 in mount output). As a result, write_to_hugetlbfs fails with ENOMEM and the test can hang waiting for progress. === Error log === # uname -r 6.12.0-xxx.el10.aarch64+64k #./charge_reserved_hugetlb.sh -cgroup-v2 # ----------------------------------------- ... # nr hugepages = 10 # writing cgroup limit: 5368709120 # writing reseravation limit: 5368709120 ... # write_to_hugetlbfs: Error mapping the file: Cannot allocate memory # Waiting for hugetlb memory reservation to reach size 2684354560. # 0 # Waiting for hugetlb memory reservation to reach size 2684354560. # 0 ... # mount |grep /mnt/huge none on /mnt/huge type hugetlbfs (rw,relatime,seclabel,pagesize=512M,size=0) # grep -i huge /proc/meminfo ... HugePages_Total: 10 HugePages_Free: 10 HugePages_Rsvd: 0 HugePages_Surp: 0 Hugepagesize: 524288 kB Hugetlb: 5242880 kB Drop the mount args with 'size=256M', so the filesystem capacity is sufficient regardless of HugeTLB page size. Link: https://lkml.kernel.org/r/20251221122639.3168038-3-liwang@redhat.com Fixes: 29750f71a9b4 ("hugetlb_cgroup: add hugetlb_cgroup reservation tests") Signed-off-by: Li Wang Acked-by: David Hildenbrand (Red Hat) Acked-by: Waiman Long Cc: Mark Brown Cc: Shuah Khan Cc: Signed-off-by: Andrew Morton Signed-off-by: Sasha Levin

selftests/mm: compaction_test: support platform with huge mount of memory

2025-06-04T12:36:58+00:00

commit ab00ddd802f80e31fc9639c652d736fe3913feae upstream. When running mm selftest to verify mm patches, 'compaction_test' case failed on an x86 server with 1TB memory. And the root cause is that it has too much free memory than what the test supports. The test case tries to allocate 100000 huge pages, which is about 200 GB for that x86 server, and when it succeeds, it expects it's large than 1/3 of 80% of the free memory in system. This logic only works for platform with 750 GB ( 200 / (1/3) / 80% ) or less free memory, and may raise false alarm for others. Fix it by changing the fixed page number to self-adjustable number according to the real number of free memory. Link: https://lkml.kernel.org/r/20250423103645.2758-1-feng.tang@linux.alibaba.com Fixes: bd67d5c15cc1 ("Test compaction of mlocked memory") Signed-off-by: Feng Tang Acked-by: Dev Jain Reviewed-by: Baolin Wang Tested-by: Baolin Wang Cc: Shuah Khan Cc: Sri Jayaramappa Cc: Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman

selftests/mm: generate a temporary mountpoint for cgroup filesystem

2025-05-02T05:41:14+00:00

[ Upstream commit 9c02223e2d9df5cb37c51aedb78f3960294e09b5 ] Currently if the filesystem for the cgroups version it wants to use is not mounted charge_reserved_hugetlb.sh and hugetlb_reparenting_test.sh tests will attempt to mount it on the hard coded path /dev/cgroup/memory, deleting that directory when the test finishes. This will fail if there is not a preexisting directory at that path, and since the directory is deleted subsequent runs of the test will fail. Instead of relying on this hard coded directory name use mktemp to generate a temporary directory to use as a mountpoint, fixing both the assumption and the disruption caused by deleting a preexisting directory. This means that if the relevant cgroup filesystem is not already mounted then we rely on having coreutils (which provides mktemp) installed. I suspect that many current users are relying on having things automounted by default, and given that the script relies on bash it's probably not an unreasonable requirement. Link: https://lkml.kernel.org/r/20250404-kselftest-mm-cgroup2-detection-v1-1-3dba6d32ba8c@kernel.org Fixes: 209376ed2a84 ("selftests/vm: make charge_reserved_hugetlb.sh work with existing cgroup setting") Signed-off-by: Mark Brown Cc: Aishwarya TCV Cc: Mark Brown Cc: Mina Almasry Cc: Shuah Khan Cc: Waiman Long Cc: Signed-off-by: Andrew Morton Signed-off-by: Sasha Levin

selftests/mm: fix incorrect buffer->mirror size in hmm2 double_map test

2024-11-08T15:22:00+00:00

[ Upstream commit 76503e1fa1a53ef041a120825d5ce81c7fe7bdd7 ] The hmm2 double_map test was failing due to an incorrect buffer->mirror size. The buffer->mirror size was 6, while buffer->ptr size was 6 * PAGE_SIZE. The test failed because the kernel's copy_to_user function was attempting to copy a 6 * PAGE_SIZE buffer to buffer->mirror. Since the size of buffer->mirror was incorrect, copy_to_user failed. This patch corrects the buffer->mirror size to 6 * PAGE_SIZE. Test Result without this patch ============================== # RUN hmm2.hmm2_device_private.double_map ... # hmm-tests.c:1680:double_map:Expected ret (-14) == 0 (0) # double_map: Test terminated by assertion # FAIL hmm2.hmm2_device_private.double_map not ok 53 hmm2.hmm2_device_private.double_map Test Result with this patch =========================== # RUN hmm2.hmm2_device_private.double_map ... # OK hmm2.hmm2_device_private.double_map ok 53 hmm2.hmm2_device_private.double_map Link: https://lkml.kernel.org/r/20240927050752.51066-1-donettom@linux.ibm.com Fixes: fee9f6d1b8df ("mm/hmm/test: add selftests for HMM") Signed-off-by: Donet Tom Reviewed-by: Muhammad Usama Anjum Cc: Jérôme Glisse Cc: Kees Cook Cc: Mark Brown Cc: Przemek Kitszel Cc: Ritesh Harjani (IBM) Cc: Shuah Khan Cc: Ralph Campbell Cc: Jason Gunthorpe Cc: Signed-off-by: Andrew Morton Signed-off-by: Sasha Levin

selftests/mm: fix charge_reserved_hugetlb.sh test

2024-10-17T13:08:18+00:00

[ Upstream commit c41a701d18efe6b8aa402efab16edbaba50c9548 ] Currently, running the charge_reserved_hugetlb.sh selftest we can sometimes observe something like: $ ./charge_reserved_hugetlb.sh -cgroup-v2 ... write_result is 0 After write: hugetlb_usage=0 reserved_usage=10485760 killing write_to_hugetlbfs Received 2. Deleting the memory Detach failure: Invalid argument umount: /mnt/huge: target is busy. Both cases are issues in the test. While the unmount error seems to be racy, it will make the test fail: $ ./run_vmtests.sh -t hugetlb ... # [FAIL] not ok 10 charge_reserved_hugetlb.sh -cgroup-v2 # exit=32 The issue is that we are not waiting for the write_to_hugetlbfs process to quit. So it might still have a hugetlbfs file open, about which umount is not happy. Fix that by making "killall" wait for the process to quit. The other error ("Detach failure: Invalid argument") does not seem to result in a test error, but is misleading. Turns out write_to_hugetlbfs.c unconditionally tries to cleanup using shmdt(), even when we only mmap()'ed a hugetlb file. Even worse, shmaddr is never even set for the SHM case. Fix that as well. With this change it seems to work as expected. Link: https://lkml.kernel.org/r/20240821123115.2068812-1-david@redhat.com Fixes: 29750f71a9b4 ("hugetlb_cgroup: add hugetlb_cgroup reservation tests") Signed-off-by: David Hildenbrand Reported-by: Mario Casquero Reviewed-by: Mina Almasry Tested-by: Mario Casquero Cc: Shuah Khan Cc: Muchun Song Signed-off-by: Andrew Morton Signed-off-by: Sasha Levin

selftests/mm: compaction_test: fix bogus test success on Aarch64

2024-07-05T07:12:24+00:00

[ Upstream commit d4202e66a4b1fe6968f17f9f09bbc30d08f028a1 ] Patch series "Fixes for compaction_test", v2. The compaction_test memory selftest introduces fragmentation in memory and then tries to allocate as many hugepages as possible. This series addresses some problems. On Aarch64, if nr_hugepages == 0, then the test trivially succeeds since compaction_index becomes 0, which is less than 3, due to no division by zero exception being raised. We fix that by checking for division by zero. Secondly, correctly set the number of hugepages to zero before trying to set a large number of them. Now, consider a situation in which, at the start of the test, a non-zero number of hugepages have been already set (while running the entire selftests/mm suite, or manually by the admin). The test operates on 80% of memory to avoid OOM-killer invocation, and because some memory is already blocked by hugepages, it would increase the chance of OOM-killing. Also, since mem_free used in check_compaction() is the value before we set nr_hugepages to zero, the chance that the compaction_index will be small is very high if the preset nr_hugepages was high, leading to a bogus test success. This patch (of 3): Currently, if at runtime we are not able to allocate a huge page, the test will trivially pass on Aarch64 due to no exception being raised on division by zero while computing compaction_index. Fix that by checking for nr_hugepages == 0. Anyways, in general, avoid a division by zero by exiting the program beforehand. While at it, fix a typo, and handle the case where the number of hugepages may overflow an integer. Link: https://lkml.kernel.org/r/20240521074358.675031-1-dev.jain@arm.com Link: https://lkml.kernel.org/r/20240521074358.675031-2-dev.jain@arm.com Fixes: bd67d5c15cc1 ("Test compaction of mlocked memory") Signed-off-by: Dev Jain Cc: Anshuman Khandual Cc: Shuah Khan Cc: Sri Jayaramappa Cc: Signed-off-by: Andrew Morton Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

selftests/mm: conform test to TAP format output

2024-07-05T07:12:24+00:00

[ Upstream commit 9a21701edc41465de56f97914741bfb7bfc2517d ] Conform the layout, informational and status messages to TAP. No functional change is intended other than the layout of output messages. Link: https://lkml.kernel.org/r/20240101083614.1076768-1-usama.anjum@collabora.com Signed-off-by: Muhammad Usama Anjum Cc: Shuah Khan Signed-off-by: Andrew Morton Stable-dep-of: d4202e66a4b1 ("selftests/mm: compaction_test: fix bogus test success on Aarch64") Signed-off-by: Sasha Levin

selftests/mm: compaction_test: fix incorrect write of zero to nr_hugepages

2024-07-05T07:12:24+00:00

[ Upstream commit 9ad665ef55eaad1ead1406a58a34f615a7c18b5e ] Currently, the test tries to set nr_hugepages to zero, but that is not actually done because the file offset is not reset after read(). Fix that using lseek(). Link: https://lkml.kernel.org/r/20240521074358.675031-3-dev.jain@arm.com Fixes: bd67d5c15cc1 ("Test compaction of mlocked memory") Signed-off-by: Dev Jain Cc: Cc: Anshuman Khandual Cc: Shuah Khan Cc: Sri Jayaramappa Signed-off-by: Andrew Morton Signed-off-by: Sasha Levin