kernel/git/stable/linux-stable.git/tools/testing/selftests, branch linux-6.6.y

kselftest/arm64: mte: Use the correct naming for tag check modes in check_hugetlb_options.c

2026-09-14T11:30:04+00:00

[ Upstream commit 7ae95109c64d64cdcf195788cf466ec0b3019a94 ] The architecture doesn't define precise/imprecise MTE tag check modes, only synchronous and asynchronous. Use the correct naming and also ensure they match the MTE_{ASYNC,SYNC}_ERR type. Fixes: 27879e8cb6b0 ("selftests: arm64: add hugetlb mte tests") Cc: Yang Shi Reviewed-by: Yang Shi Link: https://lore.kernel.org/r/20250221093331.2184245-2-catalin.marinas@arm.com Signed-off-by: Catalin Marinas Signed-off-by: Sasha Levin

kselftest/arm64: mte: Skip the hugetlb tests if MTE not supported on such mappings

2026-09-14T11:30:04+00:00

[ Upstream commit 306219d59b72cfca4005229b2c6ad43a16479e3b ] While the kselftest was added at the same time with the kernel support for MTE on hugetlb mappings, the tests may be run on older kernels. Skip the tests if PROT_MTE is not supported on MAP_HUGETLB mappings. Fixes: 27879e8cb6b0 ("selftests: arm64: add hugetlb mte tests") Cc: Yang Shi Reported-by: Naresh Kamboju Reviewed-by: Dev Jain Reviewed-by: Yang Shi Link: https://lore.kernel.org/r/20250221093331.2184245-3-catalin.marinas@arm.com Signed-off-by: Catalin Marinas Signed-off-by: Sasha Levin

selftests/arm64: Treat KSM merge_across_nodes as optional

2026-09-14T11:30:03+00:00

[ Upstream commit 1a0dba077f34a2f8faa98308d30d4b546d073145 ] The MTE KSM test requires write access to KSM sysfs but does not check that it is running as root. It also unconditionally saves, enables and restores the merge_across_nodes attribute. The kernel only creates this attribute when CONFIG_NUMA=y, so a non-NUMA kernel prints the following message three times even though every KSM subtest passes: # ERR: missing /sys/kernel/mm/ksm/merge_across_nodes Skip the test when it is not running as root. Check that the optional attribute is readable and writable, treating ENOENT as its expected absence on non-NUMA kernels and skipping the test for other access failures. Only save, enable and restore the attribute when it is available. Check MTE availability before the privilege and sysfs checks so systems without MTE retain the existing feature-unavailable skip result. This preserves the existing behavior on NUMA kernels without requiring NUMA or reducing KSM coverage on single-node systems. Fixes: f981d8fa2646 ("kselftest/arm64: Verify KSM page merge for MTE pages") Signed-off-by: Muhammad Usama Anjum Reviewed-by: Vincenzo Frascino Reviewed-by: Mark Brown Signed-off-by: Will Deacon Signed-off-by: Sasha Levin

selftests/arm64: Print missing MTE TAP headers

2026-09-14T11:30:03+00:00

[ Upstream commit 8d2237e9d6902e234bb89aabb9cd6a9e91357223 ] Most MTE tests set a TAP plan and emit results without first printing the TAP version header. Direct execution therefore starts with a plan such as "1..20" instead of "TAP version 13". The problem is particularly visible in the GCR_EL1 context-switch test. It prints its plan before forking 1,024 child processes. When stdout is fully buffered, the plan remains in the stdio buffer. Each child inherits the pending "1..1" line and flushes its copy from exit(), producing repeated plan lines. ksft_print_header() prints the TAP header and enables line buffering. Call it in every MTE test that is missing it. In the GCR_EL1 test, call it before the plan so the plan is flushed before the children are forked. In the remaining tests, call it before setup and prerequisite checks so early failures and whole-test skips also retain the header. Fixes: 29f080881601 ("kselftest/arm64: check GCR_EL1 after context switch") Signed-off-by: Muhammad Usama Anjum Reviewed-by: Vincenzo Frascino Reviewed-by: Mark Brown Signed-off-by: Will Deacon Signed-off-by: Sasha Levin

selftests: arm64: add hugetlb mte tests

2026-09-14T11:30:03+00:00

[ Upstream commit 27879e8cb6b0fdb5cdcd76685f290729309711c6 ] The tests cover mmap, mprotect hugetlb with MTE prot and COW. Signed-off-by: Yang Shi Link: https://lore.kernel.org/r/20241001225220.271178-2-yang@os.amperecomputing.com Signed-off-by: Catalin Marinas Stable-dep-of: 8d2237e9d690 ("selftests/arm64: Print missing MTE TAP headers") Signed-off-by: Sasha Levin

selftests/mm: skip COW tmpfile cases when fallocate() is unsupported

2026-09-14T11:30:01+00:00

[ Upstream commit 4004c130c358b1561a55323b0e747f20f5133f7b ] Patch series "selftests/mm: Handle unsupported and transient test conditions", v3. Several MM selftests report failures when the test environment lacks an underlying prerequisite, such as fallocate() support, MADV_REMOVE, local page-cache semantics, or swap. This series converts those unsupported cases to SKIP while preserving failures for unexpected errors. It also allows migration tests to retry transient move_pages() failures. This patch (of 4): The tmpfile-backed COW cases allocate a one-page file with fallocate() before exercising private and shared mappings. When the filesystem backing tmpfile() does not implement fallocate(), setup fails with EOPNOTSUPP and no COW behavior is exercised. This occurs when the temporary directory resides on a filesystem with limited allocation support, such as NFSv3. Reporting a failure adds noise because the test prerequisite is absent rather than the COW implementation being broken. Report EOPNOTSUPP as a skip. Continue treating every other fallocate() error as a failure so unexpected setup regressions remain visible. Link: https://lore.kernel.org/20260727095225.372655-1-usama.anjum@arm.com Link: https://lore.kernel.org/20260727095225.372655-2-usama.anjum@arm.com Fixes: f8664f3c4a08 ("selftests/vm: cow: basic COW tests for non-anonymous pages") Signed-off-by: Muhammad Usama Anjum Tested-by: Sarthak Sharma Acked-by: Usama Arif Acked-by: David Hildenbrand (Arm) Cc: Baolin Wang Cc: Barry Song Cc: Dev Jain Cc: Lance Yang Cc: Liam R. Howlett Cc: Lorenzo Stoakes Cc: Miaohe Lin Cc: Michal Hocko Cc: Mike Rapoport Cc: Naoya Horiguchi Cc: Nico Pache Cc: Ryan Roberts Cc: Shuah Khan Cc: Suren Baghdasaryan Cc: Vlastimil Babka Cc: Zi Yan Signed-off-by: Andrew Morton Signed-off-by: Sasha Levin

selftests/mm: report unique test names for each cow test

2026-09-14T11:30:01+00:00

[ Upstream commit 3f2d9a9ac544694e26c8faeb1a044c2bdcd0c793 ] The kselftest framework uses the string logged when a test result is reported as the unique identifier for a test, using it to track test results between runs. The cow test completely fails to follow this pattern, it runs test functions repeatedly with various parameters with each result report from those functions being a string logging an error message which is fixed between runs. Since the code already logs each test uniquely before it starts refactor to also print this to a buffer, then use that name as the test result. This isn't especially pretty but is relatively straightforward and is a great help to tooling. Link: https://lkml.kernel.org/r/20250527-selftests-mm-cow-dedupe-v2-3-ff198df8e38e@kernel.org Signed-off-by: Mark Brown Cc: David Hildenbrand Cc: Lorenzo Stoakes Cc: Shuah Khan Signed-off-by: Andrew Morton Stable-dep-of: 4004c130c358 ("selftests/mm: skip COW tmpfile cases when fallocate() is unsupported") Signed-off-by: Sasha Levin

selftests/mm/cow: modify the incorrect checking parameters

2026-09-14T11:30:01+00:00

[ Upstream commit bf069012df19cf80b460a03c92bfe6320dc268b0 ] In run_with_memfd_hugetlb(), some error handle have passed incorrect parameters. It should be "smem", but it was mistakenly written as "mem". Let's fix it. [gehao@kylinos.cn: fix other errant sites, per Anshuman] Link: https://lkml.kernel.org/r/20250113050908.93638-1-hao.ge@linux.dev Link: https://lkml.kernel.org/r/20250113032858.63670-1-hao.ge@linux.dev Fixes: f8664f3c4a08 ("selftests/vm: cow: basic COW tests for non-anonymous pages") Signed-off-by: Hao Ge Cc: SeongJae Park Cc: Shuah Khan (Samsung OSG) Cc: Anshuman Khandual Signed-off-by: Andrew Morton Stable-dep-of: 4004c130c358 ("selftests/mm: skip COW tmpfile cases when fallocate() is unsupported") Signed-off-by: Sasha Levin

selftests: mm: cow: flag vmsplice() hugetlb tests as XFAIL

2026-09-14T11:30:01+00:00

[ Upstream commit 4bf6a4ebc59201bcd12c932f25edda4c3e36e5df ] Patch series "selftests: mm: cow: flag vmsplice() hugetlb tests as XFAIL". The failing hugetlb vmsplice() COW tests keep confusing people, and having tests that have been failing for years and likely will keep failing for years to come because nobody cares enough is rather suboptimal. Let's mark them as XFAIL and document why fixing them is not that easy as it would appear at first sight. More details can be found in [1], especially around how hugetlb pages cannot really be overcommitted, and why we don't particularly care about these vmsplice() leaks for hugetlb -- in contrast to ordinary memory. [1] https://lore.kernel.org/all/8b42a24d-caf0-46ef-9e15-0f88d47d2f21@redhat.com/ This patch (of 2): The vmsplice() hugetlb tests have been failing right from the start, and we documented that in the introducing commit 7dad331be781 ("selftests/vm: anon_cow: hugetlb tests"): Note that some tests cases still fail. This will, for example, be fixed once vmsplice properly uses FOLL_PIN instead of FOLL_GET for pinning. With 2 MiB and 1 GiB hugetlb on x86_64, the expected failures are: Until vmsplice() is changed, these tests will likely keep failing: hugetlb COW reuse logic is harder to change, because using the same COW reuse logic as we use for !hugetlb could harm other (sane) users when running out of free hugetlb pages. More details can be found in [1], especially around how hugetlb pages cannot really be overcommitted, and why we don't particularly care about these vmsplice() leaks for hugetlb -- in contrast to ordinary memory. These (expected) failures keep confusing people, so flag them accordingly. Before: $ ./cow [...] Bail out! 8 out of 778 tests failed # Totals: pass:769 fail:8 xfail:0 xpass:0 skip:1 error:0 $ echo $? 1 After: $ ./cow [...] # Totals: pass:769 fail:0 xfail:8 xpass:0 skip:1 error:0 $ echo $? 0 [1] https://lore.kernel.org/all/8b42a24d-caf0-46ef-9e15-0f88d47d2f21@redhat.com/ Link: https://lkml.kernel.org/r/20240502085259.103784-1-david@redhat.com Link: https://lkml.kernel.org/r/20240502085259.103784-2-david@redhat.com Signed-off-by: David Hildenbrand Cc: Muchun Song Cc: Peter Xu Cc: Shuah Khan Signed-off-by: Andrew Morton Stable-dep-of: 4004c130c358 ("selftests/mm: skip COW tmpfile cases when fallocate() is unsupported") Signed-off-by: Sasha Levin

selftests/mm/cow: generalize do_run_with_thp() helper

2026-09-14T11:30:01+00:00

[ Upstream commit 12dc16b38463a671bc91dc2df10f3a014a27ff3b ] do_run_with_thp() prepares (PMD-sized) THP memory into different states before running tests. With the introduction of multi-size THP, we would like to reuse this logic to also test those smaller THP sizes. So let's add a thpsize parameter which tells the function what size THP it should operate on. A separate commit will utilize this change to add new tests for multi-size THP, where available. Link: https://lkml.kernel.org/r/20231207161211.2374093-10-ryan.roberts@arm.com Signed-off-by: Ryan Roberts Reviewed-by: David Hildenbrand Tested-by: Kefeng Wang Tested-by: John Hubbard Cc: Alistair Popple Cc: Anshuman Khandual Cc: Barry Song Cc: Catalin Marinas Cc: David Rientjes Cc: "Huang, Ying" Cc: Hugh Dickins Cc: Itaru Kitayama Cc: Kirill A. Shutemov Cc: Luis Chamberlain Cc: Matthew Wilcox (Oracle) Cc: Vlastimil Babka Cc: Yang Shi Cc: Yin Fengwei Cc: Yu Zhao Cc: Zi Yan Signed-off-by: Andrew Morton Stable-dep-of: 4004c130c358 ("selftests/mm: skip COW tmpfile cases when fallocate() is unsupported") Signed-off-by: Sasha Levin