kernel/linux.git/tools/testing/selftests/mm/guard-regions.c, branch master

selftests/mm/guard-regions: skip collapse test when thp not enabled

2026-04-18T07:10:54+00:00

Patch series "selftests/mm: skip several tests when thp is not available", v8. There are several tests requires transprarent hugepages, when run on thp disabled kernel such as realtime kernel, there will be false negative. Mark those tests as skip when thp is not available. This patch (of 6): When thp is not available, just skip the collape tests to avoid the false negative. Without the change, run with a thp disabled kernel: ./run_vmtests.sh -t madv_guard -n 1 # RUN guard_regions.anon.collapse ... # guard-regions.c:2217:collapse:Expected madvise(ptr, size, MADV_NOHUGEPAGE) (-1) == 0 (0) # collapse: Test terminated by assertion # FAIL guard_regions.anon.collapse not ok 2 guard_regions.anon.collapse # RUN guard_regions.shmem.collapse ... # guard-regions.c:2217:collapse:Expected madvise(ptr, size, MADV_NOHUGEPAGE) (-1) == 0 (0) # collapse: Test terminated by assertion # FAIL guard_regions.shmem.collapse not ok 32 guard_regions.shmem.collapse # RUN guard_regions.file.collapse ... # guard-regions.c:2217:collapse:Expected madvise(ptr, size, MADV_NOHUGEPAGE) (-1) == 0 (0) # collapse: Test terminated by assertion # FAIL guard_regions.file.collapse not ok 62 guard_regions.file.collapse # FAILED: 87 / 90 tests passed. # 17 skipped test(s) detected. Consider enabling relevant config options to improve coverage. # Totals: pass:70 fail:3 xfail:0 xpass:0 skip:17 error:0 With this change, run with thp disabled kernel: ./run_vmtests.sh -t madv_guard -n 1 # RUN guard_regions.anon.collapse ... # SKIP Transparent Hugepages not available # OK guard_regions.anon.collapse ok 2 guard_regions.anon.collapse # SKIP Transparent Hugepages not available # RUN guard_regions.file.collapse ... # SKIP Transparent Hugepages not available # OK guard_regions.file.collapse ok 62 guard_regions.file.collapse # SKIP Transparent Hugepages not available # RUN guard_regions.shmem.collapse ... # SKIP Transparent Hugepages not available # OK guard_regions.shmem.collapse ok 32 guard_regions.shmem.collapse # SKIP Transparent Hugepages not available # PASSED: 90 / 90 tests passed. # 20 skipped test(s) detected. Consider enabling relevant config options to improve coverage. # Totals: pass:70 fail:0 xfail:0 xpass:0 skip:20 error:0 Link: https://lore.kernel.org/20260402014543.1671131-1-chuhu@redhat.com Link: https://lore.kernel.org/20260402014543.1671131-2-chuhu@redhat.com Signed-off-by: Chunyu Hu Reviewed-by: Lorenzo Stoakes (Oracle) Acked-by: David Hildenbrand (Arm) Reviewed-by: Zi Yan Acked-by: Mike Rapoport (Microsoft) Cc: Li Wang Cc: Nico Pache Signed-off-by: Andrew Morton

Merge tag 'mm-nonmm-stable-2025-12-06-11-14' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2025-12-06T22:01:20+00:00

Pull non-MM updates from Andrew Morton: - "panic: sys_info: Refactor and fix a potential issue" (Andy Shevchenko) fixes a build issue and does some cleanup in ib/sys_info.c - "Implement mul_u64_u64_div_u64_roundup()" (David Laight) enhances the 64-bit math code on behalf of a PWM driver and beefs up the test module for these library functions - "scripts/gdb/symbols: make BPF debug info available to GDB" (Ilya Leoshkevich) makes BPF symbol names, sizes, and line numbers available to the GDB debugger - "Enable hung_task and lockup cases to dump system info on demand" (Feng Tang) adds a sysctl which can be used to cause additional info dumping when the hung-task and lockup detectors fire - "lib/base64: add generic encoder/decoder, migrate users" (Kuan-Wei Chiu) adds a general base64 encoder/decoder to lib/ and migrates several users away from their private implementations - "rbree: inline rb_first() and rb_last()" (Eric Dumazet) makes TCP a little faster - "liveupdate: Rework KHO for in-kernel users" (Pasha Tatashin) reworks the KEXEC Handover interfaces in preparation for Live Update Orchestrator (LUO), and possibly for other future clients - "kho: simplify state machine and enable dynamic updates" (Pasha Tatashin) increases the flexibility of KEXEC Handover. Also preparation for LUO - "Live Update Orchestrator" (Pasha Tatashin) is a major new feature targeted at cloud environments. Quoting the cover letter: This series introduces the Live Update Orchestrator, a kernel subsystem designed to facilitate live kernel updates using a kexec-based reboot. This capability is critical for cloud environments, allowing hypervisors to be updated with minimal downtime for running virtual machines. LUO achieves this by preserving the state of selected resources, such as memory, devices and their dependencies, across the kernel transition. As a key feature, this series includes support for preserving memfd file descriptors, which allows critical in-memory data, such as guest RAM or any other large memory region, to be maintained in RAM across the kexec reboot. Mike Rappaport merits a mention here, for his extensive review and testing work. - "kexec: reorganize kexec and kdump sysfs" (Sourabh Jain) moves the kexec and kdump sysfs entries from /sys/kernel/ to /sys/kernel/kexec/ and adds back-compatibility symlinks which can hopefully be removed one day - "kho: fixes for vmalloc restoration" (Mike Rapoport) fixes a BUG which was being hit during KHO restoration of vmalloc() regions * tag 'mm-nonmm-stable-2025-12-06-11-14' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (139 commits) calibrate: update header inclusion Reinstate "resource: avoid unnecessary lookups in find_next_iomem_res()" vmcoreinfo: track and log recoverable hardware errors kho: fix restoring of contiguous ranges of order-0 pages kho: kho_restore_vmalloc: fix initialization of pages array MAINTAINERS: TPM DEVICE DRIVER: update the W-tag init: replace simple_strtoul with kstrtoul to improve lpj_setup KHO: fix boot failure due to kmemleak access to non-PRESENT pages Documentation/ABI: new kexec and kdump sysfs interface Documentation/ABI: mark old kexec sysfs deprecated kexec: move sysfs entries to /sys/kernel/kexec test_kho: always print restore status kho: free chunks using free_page() instead of kfree() selftests/liveupdate: add kexec test for multiple and empty sessions selftests/liveupdate: add simple kexec-based selftest for LUO selftests/liveupdate: add userspace API selftests docs: add documentation for memfd preservation via LUO mm: memfd_luo: allow preserving memfd liveupdate: luo_file: add private argument to store runtime state mm: shmem: export some functions to internal.h ...

selftests: complete kselftest include centralization

2025-11-27T22:24:31+00:00

This follow-up patch completes centralization of kselftest.h and ksefltest_harness.h includes in remaining seltests files, replacing all relative paths with a non-relative paths using shared -I include path in lib.mk Tested with gcc-13.3 and clang-18.1, and cross-compiled successfully on riscv, arm64, x86_64 and powerpc arch. [reddybalavignesh9979@gmail.com: add selftests include path for kselftest.h] Link: https://lkml.kernel.org/r/20251017090201.317521-1-reddybalavignesh9979@gmail.com Link: https://lkml.kernel.org/r/20251016104409.68985-1-reddybalavignesh9979@gmail.com Signed-off-by: Bala-Vignesh-Reddy Suggested-by: Andrew Morton Link: https://lore.kernel.org/lkml/20250820143954.33d95635e504e94df01930d0@linux-foundation.org/ Reviewed-by: Wei Yang Cc: David Hildenbrand Cc: David S. Miller Cc: Eric Dumazet Cc: Günther Noack Cc: Jakub Kacinski Cc: Liam Howlett Cc: Lorenzo Stoakes Cc: Michal Hocko Cc: Mickael Salaun Cc: Ming Lei Cc: Paolo Abeni Cc: Shuah Khan Cc: Simon Horman Cc: Suren Baghdasaryan Cc: Vlastimil Babka Signed-off-by: Andrew Morton

tools/testing/selftests/mm: add smaps visibility guard region test

2025-11-20T21:43:58+00:00

Assert that we observe guard regions appearing in /proc/$pid/smaps as expected, and when split/merge is performed too (with expected sticky behaviour). Also add handling for file systems which don't sanely handle mmap() VMA merging so we don't incorrectly encounter a test failure in this situation. Link: https://lkml.kernel.org/r/059e62b8c67e55e6d849878206a95ea1d7c1e885.1763460113.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes Cc: Andrei Vagin Cc: Baolin Wang Cc: Barry Song Cc: David Hildenbrand (Red Hat) Cc: Dev Jain Cc: Jann Horn Cc: Jonathan Corbet Cc: Lance Yang Cc: Liam Howlett Cc: "Masami Hiramatsu (Google)" Cc: Mathieu Desnoyers Cc: Michal Hocko Cc: Mike Rapoport Cc: Nico Pache Cc: Pedro Falcato Cc: Ryan Roberts Cc: Steven Rostedt Cc: Suren Baghdasaryan Cc: Vlastimil Babka Cc: Zi Yan Signed-off-by: Andrew Morton

tools/testing/selftests/mm: add MADV_COLLAPSE test case

2025-11-20T21:43:58+00:00

To ensure the retract_page_tables() logic functions correctly with the introduction of VM_MAYBE_GUARD, add a test to assert that madvise collapse fails when guard regions are established in the collapsed range in all cases. Unfortunately we cannot differentiate between e.g. CONFIG_READ_ONLY_THP_FOR_FS not being set vs. a file-backed VMA having collapse correctly disallowed, so in each instance we will get an assert pass here. We add an additional check to see whether guard regions are preserved across collapse in case of a bug causing the collapse to succeed, which will give us more data to debug with should this occur in future. Link: https://lkml.kernel.org/r/0748beeb864525b8ddfa51adad7128dd32eb3ac4.1763460113.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes Cc: Andrei Vagin Cc: Baolin Wang Cc: Barry Song Cc: David Hildenbrand (Red Hat) Cc: Dev Jain Cc: Jann Horn Cc: Jonathan Corbet Cc: Lance Yang Cc: Liam Howlett Cc: "Masami Hiramatsu (Google)" Cc: Mathieu Desnoyers Cc: Michal Hocko Cc: Mike Rapoport Cc: Nico Pache Cc: Pedro Falcato Cc: Ryan Roberts Cc: Steven Rostedt Cc: Suren Baghdasaryan Cc: Vlastimil Babka Cc: Zi Yan Signed-off-by: Andrew Morton

selftests/mm: fix FORCE_READ to read input value correctly

2025-08-28T05:45:42+00:00

FORCE_READ() converts input value x to its pointer type then reads from address x. This is wrong. If x is a non-pointer, it would be caught it easily. But all FORCE_READ() callers are trying to read from a pointer and FORCE_READ() basically reads a pointer to a pointer instead of the original typed pointer. Almost no access violation was found, except the one from split_huge_page_test. Fix it by implementing a simplified READ_ONCE() instead. Link: https://lkml.kernel.org/r/20250805175140.241656-1-ziy@nvidia.com Fixes: 3f6bfd4789a0 ("selftests/mm: reuse FORCE_READ to replace "asm volatile("" : "+r" (XXX));"") Signed-off-by: Zi Yan Reviewed-by: Lorenzo Stoakes Acked-by: David Hildenbrand Reviewed-by: wang lian Reviewed-by: Wei Yang Cc: Christian Brauner Cc: Jann Horn Cc: Kairui Song Cc: Liam Howlett Cc: Mark Brown Cc: SeongJae Park Cc: Shuah Khan Cc: Vlastimil Babka Cc: Zi Yan Signed-off-by: Andrew Morton

selftests/mm: guard-regions: Use SKIP() instead of ksft_exit_skip()

2025-07-25T02:12:42+00:00

To ensure only the current test is skipped on permission failure, instead of terminating the entire test binary. Link: https://lkml.kernel.org/r/20250717131857.59909-3-lianux.mm@gmail.com Signed-off-by: wang lian Reviewed-by: Lorenzo Stoakes Acked-by: David Hildenbrand Reviewed-by: Mark Brown Reviewed-by: Zi Yan Reviewed-by: Wei Yang Cc: Christian Brauner Cc: Jann Horn Cc: Kairui Song Cc: Liam Howlett Cc: SeongJae Park Cc: Shuah Khan Cc: Vlastimil Babka Signed-off-by: Andrew Morton

selftests/mm: reuse FORCE_READ to replace "asm volatile("" : "+r" (XXX));"

2025-07-25T02:12:41+00:00

Patch series "selftests/mm: reuse FORCE_READ to replace "asm volatile("" : "+r" (XXX));" and some cleanup", v2. This series introduces a common FORCE_READ() macro to replace the cryptic asm volatile("" : "+r" (variable)); construct used in several mm selftests. This improves code readability and maintainability by removing duplicated, hard-to-understand code. This patch (of 2): Several mm selftests use the `asm volatile("" : "+r" (variable));` construct to force a read of a variable, preventing the compiler from optimizing away the memory access. This idiom is cryptic and duplicated across multiple test files. Following a suggestion from David[1], this patch refactors this common pattern into a FORCE_READ() macro Link: https://lkml.kernel.org/r/20250717131857.59909-1-lianux.mm@gmail.com Link: https://lkml.kernel.org/r/20250717131857.59909-2-lianux.mm@gmail.com Link: https://lore.kernel.org/lkml/4a3e0759-caa1-4cfa-bc3f-402593f1eee3@redhat.com/ [1] Signed-off-by: wang lian Reviewed-by: Lorenzo Stoakes Acked-by: David Hildenbrand Reviewed-by: Zi Yan Reviewed-by: Wei Yang Cc: Christian Brauner Cc: Jann Horn Cc: Kairui Song Cc: Liam Howlett Cc: Mark Brown Cc: SeongJae Park Cc: Shuah Khan Cc: Vlastimil Babka Signed-off-by: Andrew Morton

selftests/mm: skip guard_regions.uffd tests when uffd is not present

2025-06-01T05:46:11+00:00

Patch series "Skip mm selftests instead when kernel features are not present", v2. Two guard_regions tests on userfaultfd fail when userfaultfd is not present. Skip them instead. hugevm test reads kernel config to get page table level information and fails when neither /proc/config.gz nor /boot/config-* is present. Skip it instead. This patch (of 2): When userfaultfd is not compiled into kernel, userfaultfd() returns -1, causing guard_regions.uffd tests to fail. Skip the tests instead. Link: https://lkml.kernel.org/r/20250516132938.356627-1-ziy@nvidia.com Link: https://lkml.kernel.org/r/20250516132938.356627-2-ziy@nvidia.com Signed-off-by: Zi Yan Reviewed-by: Lorenzo Stoakes Reviewed-by: Pedro Falcato Cc: Adam Sindelar Signed-off-by: Andrew Morton

selftests/mm: add PAGEMAP_SCAN guard region test

2025-05-12T00:48:17+00:00

Add a selftest to verify the PAGEMAP_SCAN ioctl correctly reports guard regions using the newly introduced PAGE_IS_GUARD flag. Link: https://lkml.kernel.org/r/20250324065328.107678-4-avagin@google.com Signed-off-by: Andrei Vagin Reviewed-by: Lorenzo Stoakes Cc: David Hildenbrand Cc: Jonathan Corbet Cc: Shuah Khan Signed-off-by: Andrew Morton