linux.git/tools/testing/selftests/mm/Makefile, branch master

selftests: mm: test kmemleak's N-consecutive-scan leak confirmation

2026-08-25T01:43:18+00:00

Add a functional test for the min_unref_scans kmemleak module parameter. 
Using samples/kmemleak's helper module it checks that min_unref_scans=1
reports an orphan on the first scan, min_unref_scans=2 reports nothing on
the first scan but does on the second, and that the parameter reads back
what was written.

It counts only the helper module's own orphans (matched by their
[kmemleak_test] backtrace, with the module kept loaded so the symbols
resolve) so unrelated leaks already present on the system do not perturb
the result.  The test skips when run as non-root, without
CONFIG_DEBUG_KMEMLEAK / CONFIG_SAMPLE_KMEMLEAK, on a kernel without the
parameter, or when the helper yields no detectable orphan.

Link: https://lore.kernel.org/20260713-catalin_pto-v1-4-5b93b1131089@debian.org
Signed-off-by: Breno Leitao 
Reviewed-by: Catalin Marinas 
Cc: David Hildenbrand 
Cc: Geert Uytterhoeven 
Cc: Jonathan Corbet 
Cc: Liam R. Howlett 
Cc: Lorenzo Stoakes 
Cc: Michal Hocko 
Cc: Mike Rapoport 
Cc: Shuah Khan 
Cc: Suren Baghdasaryan 
Cc: Vlastimil Babka 
Signed-off-by: Andrew Morton

selftests/mm: rename local_config.h to local_config.h_gen

2026-08-25T01:43:01+00:00

Patch series "selftests/mm: use pattern matching in .gitignore", v4.

The current selftests/mm/.gitignore hardcodes each generated test binary
by name, which requires manual updates every time a new test is added.

This series switches to a pattern-matching approach (similar to KVM
selftests), ignoring everything by default and allowing specific source
extensions.  To accommodate this without tracking generated headers,
local_config.h is renamed to local_config.h_gen.


This patch (of 2):

Because local_config.h is a generated build artifact, un-ignoring all .h
files in .gitignore causes it to incorrectly show up as an untracked file
in git status.

Rename it to local_config.h_gen so it no longer matches the !*.h inclusion
rule, preparing for a subsequent patch that switches .gitignore to a
pattern-matching approach.

Update Makefile, check_config.sh, and affected test sources (cow.c,
gup_longterm.c) accordingly.

Link: https://lore.kernel.org/20260803221732.3651981-1-pratmal@google.com
Link: https://lore.kernel.org/20260803221732.3651981-2-pratmal@google.com
Signed-off-by: Pratyush Mallick 
Reviewed-by: Lorenzo Stoakes 
Acked-by: Mike Rapoport (Microsoft) 
Suggested-by: David Hildenbrand 
Cc: Jason Gunthorpe 
Cc: John Hubbard 
Cc: "Liam R. Howlett" 
Cc: Michal Hocko 
Cc: Peter Xu 
Cc: SeongJae Park 
Cc: Shuah Khan 
Cc: Suren Baghdasaryan 
Cc: Vlastimil Babka 
Cc: Yosry Ahmed 
Signed-off-by: Andrew Morton

selftests/mm: remove obsolete hugetlb vmemmap test

2026-08-05T02:19:05+00:00

The hugetlb vmemmap selftest was added to check the old HVO layout where
tail vmemmap pages reused the head page.  That assumption no longer
matches the current HVO mapping layout.

HVO now keeps a private backing page for the head vmemmap page and remaps
redundant tail vmemmap pages to a shared read-only backing page.  The old
page flag check is therefore testing an obsolete implementation detail
rather than the current ABI or behavior.

Remove the stale test and its build and run entries.

[akpm@linux-foundation.org: don't clean old executables out of .gitignore]
  Link: https://lore.kernel.org/CAHk-=wiHK5_oBUdUiNAaevmN9f-ORe+QBqbRefAZaw-RbgEn3w@mail.gmail.com
Link: https://lore.kernel.org/20260710092427.3459121-1-songmuchun@bytedance.com
Signed-off-by: Muchun Song 
Reviewed-by: Lorenzo Stoakes 
Acked-by: David Hildenbrand (Arm) 
Reviewed-by: SJ Park 
Cc: Liam R. Howlett 
Cc: Michal Hocko 
Cc: Mike Rapoport 
Cc: Muchun Song 
Cc: Shuah Khan 
Cc: Suren Baghdasaryan 
Cc: Vlastimil Babka 
Signed-off-by: Andrew Morton

selftests/mm: rename thp_settings.[ch] to hugepage_settings.[ch]

2026-06-21T18:37:23+00:00

...  for upcoming addition of HugeTLB helpers.

Link: https://lore.kernel.org/20260511162840.375890-24-rppt@kernel.org
Signed-off-by: Mike Rapoport (Microsoft) 
Tested-by: Luiz Capitulino 
Tested-by: Sarthak Sharma 
Cc: Baolin Wang 
Cc: Barry Song 
Cc: David Hildenbrand 
Cc: Dev Jain 
Cc: Donet Tom 
Cc: Jason Gunthorpe 
Cc: John Hubbard 
Cc: Lance Yang 
Cc: Leon Romanovsky 
Cc: Liam Howlett 
Cc: Li Wang 
Cc: Lorenzo Stoakes 
Cc: Mark Brown 
Cc: Michal Hocko 
Cc: Nico Pache 
Cc: Peter Xu 
Cc: Ryan Roberts 
Cc: Shuah Khan 
Cc: Suren Baghdasaryan 
Cc: Vlastimil Babka 
Cc: Zi Yan 
Signed-off-by: Andrew Morton

selftests/mm: rename hugepage-* tests to hugetlb-*

2026-06-21T18:37:19+00:00

hugepage could mean both THP and HugeTLB these days.

Rename hugepage-* tests for HugeTLB to hugetlb-* to avoid confusion.

Make sure that Makefile update keeps alphabetical ordering of the
TEST_GEN_FILES entries.

Keep old binary names in .gitignore because Linus prefers it this way.

Link: https://lore.kernel.org/20260511162840.375890-8-rppt@kernel.org
Signed-off-by: Mike Rapoport (Microsoft) 
Reviewed-by: Donet Tom 
Reviewed-by: Li Wang 
Tested-by: Sarthak Sharma 
Tested-by: Luiz Capitulino 
Cc: Baolin Wang 
Cc: Barry Song 
Cc: David Hildenbrand 
Cc: Dev Jain 
Cc: Jason Gunthorpe 
Cc: John Hubbard 
Cc: Lance Yang 
Cc: Leon Romanovsky 
Cc: Liam Howlett 
Cc: Lorenzo Stoakes 
Cc: Mark Brown 
Cc: Michal Hocko 
Cc: Nico Pache 
Cc: Peter Xu 
Cc: Ryan Roberts 
Cc: Shuah Khan 
Cc: Suren Baghdasaryan 
Cc: Vlastimil Babka 
Cc: Zi Yan 
Signed-off-by: Andrew Morton

selftests/mm: merge map_hugetlb into hugepage-mmap

2026-06-21T18:37:18+00:00

Both tests create a hugettlb mapping, fill it with data and verify the
data, the only difference is that one uses file-backed memory and another
one uses anonymous memory.

Merge both tests into a single file.

Link: https://lore.kernel.org/20260511162840.375890-7-rppt@kernel.org
Signed-off-by: Mike Rapoport (Microsoft) 
Reviewed-by: Luiz Capitulino 
Reviewed-by: Donet Tom 
Tested-by: Luiz Capitulino 
Cc: Baolin Wang 
Cc: Barry Song 
Cc: David Hildenbrand 
Cc: Dev Jain 
Cc: Jason Gunthorpe 
Cc: John Hubbard 
Cc: Lance Yang 
Cc: Leon Romanovsky 
Cc: Liam Howlett 
Cc: Li Wang 
Cc: Lorenzo Stoakes 
Cc: Mark Brown 
Cc: Michal Hocko 
Cc: Nico Pache 
Cc: Peter Xu 
Cc: Ryan Roberts 
Cc: Sarthak Sharma 
Cc: Shuah Khan 
Cc: Suren Baghdasaryan 
Cc: Vlastimil Babka 
Cc: Zi Yan 
Signed-off-by: Andrew Morton

selftests/mm: add kmemleak verbose dedup test

2026-05-29T04:05:09+00:00

Add a regression test for the per-scan verbose dedup added in the
preceding commit.  The test loads samples/kmemleak's helper module
(CONFIG_SAMPLE_KMEMLEAK=m) to generate orphan allocations, several of
which share an allocation backtrace, runs four kmemleak scans with verbose
printing enabled, then walks dmesg looking for two "unreferenced object"
reports within a single scan that share an identical backtrace - which
would mean dedup failed to collapse them.

The test is intentionally permissive on detection but strict on
regressions:

 - PASS when no duplicates are observed, regardless of whether the
   dedup summary line ("... and N more object(s) with the same
   backtrace") was actually emitted. Per-CPU chunk reuse, slab
   freelist pointers, kernel stack residue and CONFIG_DEBUG_KMEMLEAK_
   AUTO_SCAN can all keep most of the orphans "still referenced" or
   reported across many separate scans, so the dedup path may have
   nothing to fold within one scan. That is not a regression.

 - PASS reports whether dedup actually fired, so a passing run on a
   well-behaved environment is still informative.

 - FAIL when two same-backtrace reports land in a single scan (clear
   dedup regression).

 - FAIL when kmemleak's own per-scan tally counts leaks but the
   verbose path emits zero "unreferenced object" lines - that catches
   a regression in the verbose printer itself, which would otherwise
   pass the duplicate check trivially.

 - SKIP when kmemleak is absent, disabled at runtime, or the helper
   module is not built.

The dmesg parser anchors stack-frame matching to the indentation kmemleak
uses for them (4+ spaces under "kmemleak: ") so unrelated kmemleak
warnings landing between reports do not get lumped into the backtrace key
and mask a duplicate.

Link: https://lore.kernel.org/20260506-kmemleak_dedup-v3-2-2d36aafc34da@debian.org
Signed-off-by: Breno Leitao 
Cc: Catalin Marinas 
Cc: David Hildenbrand 
Cc: Liam R. Howlett 
Cc: Lorenzo Stoakes 
Cc: Michal Hocko 
Cc: Mike Rapoport 
Cc: Shuah Khan 
Cc: Suren Baghdasaryan 
Cc: Vlastimil Babka 
Signed-off-by: Andrew Morton

selftests/mm: suppress compiler error in liburing check

2026-05-29T04:04:39+00:00

When building the mm selftests on a system without liburing development
headers, check_config.sh leaks a raw compiler error:

  /tmp/tmp.kIIOIqwe3n.c:2:10: fatal error: liburing.h: No such file or directory
      2 | #include 
        |          ^~~~~~~~~~~~

Since this is an expected failure during the configuration probe,
redirect the compiler output to /dev/null to hide it.

And the build system prints a clear warning when this occurs:

  Warning: missing liburing support. Some tests will be skipped.

Because the user is properly notified about the missing dependency, the
raw compiler error is redundant and only confuse users.

Additionally, update the Makefile to use $(Q) and $(call msg,...) for the
check_config.sh execution.  This aligns the probe with standard kbuild
output formatting, providing a clean "CHK" message instead of printing the
raw command during the build.

Link: https://lore.kernel.org/20260422080446.26020-3-wangli.ahau@gmail.com
Signed-off-by: Li Wang 
Tested-by: David Hildenbrand (Arm) 
Acked-by: David Hildenbrand (Arm) 
Cc: Liam Howlett 
Cc: Lorenzo Stoakes 
Cc: Michal Hocko 
Cc: Mike Rapoport 
Cc: Shuah Khan 
Cc: Suren Baghdasaryan 
Cc: Vlastimil Babka 
Signed-off-by: Andrew Morton

selftests/mm: respect build verbosity settings for 32/64-bit targets

2026-05-29T04:04:38+00:00

Patch series "selftests/mm: clean up build output and verbosity", v3.

Currently, the build process for the mm selftests is unnecessarily noisy.

First, it leaks raw compiler errors during the liburing feature probe if
the headers are missing, which is confusing since the build system already
handles this gracefully with a clear warning.

Second, the specific 32-bit and 64-bit compilation targets ignore the
standard kbuild verbosity settings, always printing their full compiler
commands even during a default quiet build.


This patch (of 2):

The 32-bit and 64-bit compilation rules invoke $(CC) directly, bypassing
the $(Q) quiet prefix and $(call msg,...) helper used by the rest of the
selftests build system.  This causes these rules to always print the full
compiler command line, even when V=0 (the default).

Wrap the commands with $(Q) and $(call msg,CC,,$@) to match the convention
used by lib.mk, so that quiet and verbose builds behave consistently
across all targets.

==== Build logs ====
  ...
  CC       merge
  CC       rmap
  CC       soft-dirty
  gcc -Wall -O2 -I /usr/src/25/tools/testing/selftests/../../..
                -isystem /usr/src/25/tools/testing/selftests/../../../usr/include
                -isystem /usr/src/25/tools/testing/selftests/../../../tools/include/uapi
                -Wunreachable-code -U_FORTIFY_SOURCE -no-pie -D_GNU_SOURCE=
                -I/usr/src/25/tools/testing/selftests/../../../tools/testing/selftests
                -m32 -mxsave  protection_keys.c vm_util.c thp_settings.c pkey_util.c
                -lrt -lpthread -lm -lrt -ldl -lm
                -o /usr/src/25/tools/testing/selftests/mm/protection_keys_32
  gcc -Wall -O2 -I /usr/src/25/tools/testing/selftests/../../..
                -isystem /usr/src/25/tools/testing/selftests/../../../usr/include
                -isystem /usr/src/25/tools/testing/selftests/../../../tools/include/uapi
                -Wunreachable-code -U_FORTIFY_SOURCE -no-pie -D_GNU_SOURCE=
                -I/usr/src/25/tools/testing/selftests/../../../tools/testing/selftests
                -m32 -mxsave  pkey_sighandler_tests.c vm_util.c thp_settings.c pkey_util.c
                -lrt -lpthread -lm -lrt -ldl -lm
                -o /usr/src/25/tools/testing/selftests/mm/pkey_sighandler_tests_32
  ...

Link: https://lore.kernel.org/20260422080446.26020-1-wangli.ahau@gmail.com
Link: https://lore.kernel.org/20260422080446.26020-2-wangli.ahau@gmail.com
Signed-off-by: Li Wang 
Reported-by: Andrew Morton 
Tested-by: Andrew Morton 
Tested-by: David Hildenbrand (Arm) 
Acked-by: David Hildenbrand (Arm) 
Cc: Liam Howlett 
Cc: Lorenzo Stoakes 
Cc: Michal Hocko 
Cc: Mike Rapoport 
Cc: Shuah Khan 
Cc: Suren Baghdasaryan 
Cc: Vlastimil Babka 
Signed-off-by: Andrew Morton

selftests/mm: add folio_split() and filemap_get_entry() race test

2026-04-05T20:53:36+00:00

The added folio_split_race_test is a modified C port of the race condition
test from [1].  The test creates shmem huge pages, where the main thread
punches holes in the shmem to cause folio_split() in the kernel and a set
of 16 threads reads the shmem to cause filemap_get_entry() in the kernel. 
filemap_get_entry() reads the folio and xarray split by folio_split()
locklessly.  The original test[2] is written in rust and uses memfd (shmem
backed).  This C port uses shmem directly and use a single process.

Note: the initial rust to C conversion is done by Cursor.

Link: https://lore.kernel.org/all/CAKNNEtw5_kZomhkugedKMPOG-sxs5Q5OLumWJdiWXv+C9Yct0w@mail.gmail.com/ [1]
Link: https://github.com/dfinity/thp-madv-remove-test [2]
Link: https://lkml.kernel.org/r/20260323163717.184107-1-ziy@nvidia.com
Co-developed-by: Bas van Dijk 
Signed-off-by: Bas van Dijk 
Co-developed-by: Adam Bratschi-Kaye 
Signed-off-by: Adam Bratschi-Kaye 
Signed-off-by: Zi Yan 
Cc: Baolin Wang 
Cc: Barry Song 
Cc: David Hildenbrand 
Cc: Dev Jain 
Cc: Hugh Dickins 
Cc: Lance Yang 
Cc: Liam Howlett 
Cc: Lorenzo Stoakes 
Cc: Matthew Wilcox (Oracle) 
Cc: Michal Hocko 
Cc: Mike Rapoport 
Cc: Nico Pache 
Cc: Ryan Roberts 
Cc: Shuah Khan 
Cc: Suren Baghdasaryan 
Cc: Vlastimil Babka 
Signed-off-by: Andrew Morton