linux-stable.git/tools/testing, branch v7.2.6

selftests/arm64: Fix MTE prctl TAP plan

2026-09-14T11:41:09+00:00

[ Upstream commit bb52892f9234e4ecd982fa51222aab33ce282f79 ]

The MTE prctl test emits one result from check_basic_read() followed by
one result for each of the seven entries in mte_modes[]. However, the TAP
plan only accounts for the array entries, producing:

  # Planned tests != run tests (7 != 8)

Include the basic read check in the plan so that all eight emitted results
are declared.

Reviewed-by: Mark Brown 
Fixes: 1f488fb91378 ("kselftest/arm64/mte: Add MTE_STORE_ONLY testcases")
Signed-off-by: Muhammad Usama Anjum 
Reviewed-by: Vincenzo Frascino 
Signed-off-by: Will Deacon 
Signed-off-by: Sasha Levin

selftests/arm64: Treat KSM merge_across_nodes as optional

2026-09-14T11:41:09+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

2026-09-14T11:41:09+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/proc: make proc-maps-race work with READ_IMPLIES_EXEC

2026-09-14T11:41:07+00:00

[ Upstream commit 0685630fdccb62dcb0e3f44525a40578da5f6dc8 ]

test_maps_tearing_from_split times out when READ_IMPLIES_EXEC is set.
This happens by default on pre-ARMv6 CPUs, which lack no-execute support.

split_vma() re-maps the first page with mod_info->prot | PROT_EXEC to make
it differ from its neighbours.  With READ_IMPLIES_EXEC the original
mapping is already executable, so no split occurs and the test hangs
waiting for the modifier child.

Use PROT_NONE for the split mapping, which always differs from its
readable neighbours.

Link: https://lore.kernel.org/20260808200312.6326-1-kmehltretter@gmail.com
Fixes: beb69e817246 ("selftests/proc: add /proc/pid/maps tearing from vma split test")
Assisted-by: Codex:gpt-5.6-terra
Signed-off-by: Karl Mehltretter 
Acked-by: Suren Baghdasaryan 
Cc: Alexey Dobriyan 
Cc: Jann Horn 
Cc: Liam R. Howlett 
Cc: Shuah Khan 
Cc: Vlastimil Babka 
Signed-off-by: Andrew Morton 
Signed-off-by: Sasha Levin

selftests/mm: fix read_file() return value check

2026-09-14T11:41:06+00:00

[ Upstream commit 4050b5b0b60c93160a816d68ea1eb9ae92739a73 ]

read_file() returns 0 on open/read failures and never returns negative
values.  Existing < 0 error checks never trigger, so read failures are
silently ignored.  Check for zero return to detect read_file() failures.

Also fix misleading error message in get_finfo().  The error string
incorrectly references read_num when reading uevent files.

Link: https://lore.kernel.org/20260807013555.36525-1-hongfu.li@linux.dev
Fixes: e0c13f9761df ("khugepaged: add self test")
Signed-off-by: Hongfu Li 
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: Michal Hocko 
Cc: Mike Rapoport 
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: skip COW tmpfile cases when fallocate() is unsupported

2026-09-14T11:41:06+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/bpf: Retry stat generation in cgroup_iter_memcg

2026-09-14T11:40:52+00:00

[ Upstream commit 3d9393ff98ca9a132c7a0778436f5ed856fb3dc6 ]

Each cgroup_iter_memcg subtest touches 1024 pages and expects the matching
memcg counter to be non-zero. On a host with many CPUs it reads zero
instead:

  test_anon:FAIL:final anon mapped val: actual 0 <= expected 0

memcg stats are cached per-cpu and only become visible once the periodic
flusher runs (FLUSH_TIME, 2s), or once pending updates cross
MEMCG_CHARGE_BATCH * num_online_cpus(). That threshold is 512 pages at 8
CPUs but 8192 at 128, so a single pass no longer reaches it and
bpf_mem_cgroup_flush_stats() returns without flushing anything.

Retry the stat generation, sleeping in between, so that a flusher cycle is
always covered. Sleep before dropping the mapping, so that a flusher cycle
landing in the sleep observes the mapped state. nr_anon_mapped and
nr_file_mapped are rmap gauges, and unmapping first would post a matching
negative delta for the flusher to aggregate to a net zero.

test_file asserts on both nr_file_pages and nr_file_mapped, which have
different lifetimes, as page cache pages outlive the mapping. Retry
while either one is still zero.

Fixes: 6bce6ddbe634 ("bpf: selftests: selftests for memcg stat kfuncs")
Signed-off-by: Andrii Nakryiko 
Signed-off-by: Daniel Borkmann 
Link: https://lore.kernel.org/bpf/20260814232017.2839959-1-andrii@kernel.org
Signed-off-by: Sasha Levin

selftests/mm: thuge-gen: fix test_shmget() for PAGE_SIZE check

2026-09-14T11:40:49+00:00

[ Upstream commit 08745c62350126bc31b09548137be87e2866f628 ]

Commit 49a4e7186b08 ("selftests/mm: thuge-gen: add setup of HugeTLB
pages") changed thuge-gen test to use common functions for reading hugetlb
attributes from sysfs, but it missed that the original read_free()
function special cased PAGE_SIZE tests.

For PAGE_SIZE tests, failure to read sysfs was ignored and read_free()
returned 0.

This allowed test_shmget() to essentially skip the check of how many huge
pages was consumed when it ran with PAGE_SIZE.

Commit 3199b0c09efa ("selftests/mm: fix read_file() return value check")
fixed checks for read_file() return value and this exposed the issue in
test_shmget() that checks the number of free hugetlb pages even for
PAGE_SIZE test, tries to access

/sys/kernel/mm/hugepages/hugepages-/free_hugepages

and obviously fails there.

Gate the checks for free huge pages on size != getpagesize() and
initialize before and after variables to values matching PAGE_SIZE test.

Link: https://lore.kernel.org/20260812-selftests-thuge-gen-fix-v2-1-9adaa693e73b@kernel.org
Fixes: 49a4e7186b08 ("selftests/mm: thuge-gen: add setup of HugeTLB pages")
Acked-by: David Hildenbrand (Arm) 
Reviewed-by: Sarthak Sharma 
Acked-by: Lorenzo Stoakes (ARM) 
Signed-off-by: Mike Rapoport (Microsoft) 
Cc: Liam R. Howlett 
Cc: Michal Hocko 
Cc: Shuah Khan 
Cc: Suren Baghdasaryan 
Cc: Vlastimil Babka 
Signed-off-by: Andrew Morton 
Signed-off-by: Sasha Levin

selftests/sched_ext: Fix flaky ddsp failure tests on busy systems

2026-09-14T11:40:47+00:00

[ Upstream commit e72979d3264a87a6a2dfb44fe0f5723a17d2ef84 ]

The ddsp_vtimelocal_fail and ddsp_bogus_dsq_fail tests skip calling
scx_bpf_dsq_insert_vtime() if scx_bpf_pick_idle_cpu() fails to find an idle
CPU (returns a negative error code). On loaded systems, this results in the
tests skipping the very assertions they are meant to verify.

Eliminate this flakiness by falling back to prev_cpu if no idle CPU is
found, ensuring the illegal dispatch operations are unconditionally
attempted and tested.

Fixes: a5db7817af78 ("sched_ext: Add selftests")
Signed-off-by: Michal Blaszczyk 
Signed-off-by: Tejun Heo 
Signed-off-by: Sasha Levin

selftests/bpf: Fix selftest build after filter.h update

2026-09-14T11:40:47+00:00

[ Upstream commit a2b83a8c8430b5a4cb43a1671c62535afcfce78d ]

Upstream commit 7a1f400ff5e5 ("tools: Ensure tools copy of
linux/filter.h exports the UAPI") caused selftests/bpf build to
fail [1] with:

  In file included from progs/arena_atomics.c:9:
  /codebuild/output/src2365462129/src/actions-runner/_work/bpf/bpf/tools/testing/selftests/bpf/../../../include/linux/filter.h:9:10: fatal error: 'uapi/linux/filter.h' file not found
      9 | #include 
        |          ^~~~~~~~~~~~~~~~~~~~~
  1 error generated.
    CLNG-BPF [test_progs] bind_perm.bpf.o
  make: *** [Makefile:888: /codebuild/output/src2365462129/src/actions-runner/_work/bpf/bpf/tools/testing/selftests/bpf/arena_atomics.bpf.o] Error 1
  make: *** Waiting for unfinished jobs....
    GEN-OBJ  [libarena] libarena.bpf.o
    GEN-SKEL [libarena] libarena.skel.h
  make: Leaving directory '/codebuild/output/src2365462129/src/actions-runner/_work/bpf/bpf/tools/testing/selftests/bpf'
  Process completed with exit code 2.

BPF selftest programs include the tools header directly, but
BPF_CFLAGS only exposes tools/include/uapi. Compiler therefore cannot
resolve the nested UAPI include.

Add tools/include after tools/include/uapi in BPF_CFLAGS. This
preserves the existing UAPI header precedence while allowing tools
headers to include uapi headers.

[1] https://github.com/kernel-patches/bpf/actions/runs/31806678733/job/94787271162

Fixes: 7a1f400ff5e5 ("tools: Ensure tools copy of linux/filter.h exports the UAPI")
Signed-off-by: Ihor Solodrai 
Signed-off-by: Andrii Nakryiko 
Link: https://lore.kernel.org/bpf/20260814173522.2783625-1-ihor.solodrai@linux.dev
Signed-off-by: Sasha Levin