selftests/futex: Give circular-list nodes static storage

The registered robust-list head has static storage but points at three
automatic lock nodes. GCC warns about storing the address of a local
v

selftests/futex: Give circular-list nodes static storage

The registered robust-list head has static storage but points at three
automatic lock nodes. GCC warns about storing the address of a local
variable in the static head when building the selftest with -Wall.

Give the nodes static storage as well. This keeps every object in the
circular list alive through child exit without changing the list topology.

Signed-off-by: Miles Krause <mileskrause5200@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Reviewed-by: André Almeida <andrealmeid@igalia.com>
Link: https://patch.msgid.link/20260711-futex-robust-list-static-nodes-v1-1-723754d75cf5@gmail.com

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selftests/futex: Use thread synchronization helpers instead of usleep()

This test uses usleep() to delay the main thread after creating the test
thread[s] under the assumption that they already are

selftests/futex: Use thread synchronization helpers instead of usleep()

This test uses usleep() to delay the main thread after creating the test
thread[s] under the assumption that they already are blocked on the futex
when the main thread continues.

That "works" on otherwise idle systems, but fails under load resulting in
failed selftests because the requeue operation starts before the waiters
reached the kernel.

Replace the usleep() waits by the new thread synchronization helpers to cure that.

[ tglx: Adapted to test harness changes, fixed coding style, sanitized the
timeout handling and rewrote change log.

Co-developed-by: Edward Liaw <edliaw@google.com>
Signed-off-by: Yuwen Chen <ywen.chen@foxmail.com>
Signed-off-by: Edward Liaw <edliaw@google.com>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Link: https://patch.msgid.link/tencent_76B9DE9C9FE5C57F6D74B5149970DF8CCF0A@qq.com

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selftests/futex: Provide thread creation and synchronization helpers

There are timing issues in the use of threads in some selftests for futexes
as the tests rely on timed waits to ensure that the o

selftests/futex: Provide thread creation and synchronization helpers

There are timing issues in the use of threads in some selftests for futexes
as the tests rely on timed waits to ensure that the other test thread[s]
reached the lock wait function in the kernel.

That "works" on halfways idle systems, but fails under load which results
in tests failing.

Provide a set of helper functions to create test threads and to wait for
them to reach the lock wait by monitoring /proc/$PID/wchan.

[ tglx: Fixup coding style, move the timeout into the helper, adapt to test
harness changes and massage change log ]

Signed-off-by: Yuwen Chen <ywen.chen@foxmail.com>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Link: https://patch.msgid.link/tencent_4C90BE98BBC48B38B9FBC6A95C45CF49F309@qq.com

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selftests/futex: Dynamically skip unsupported tests

Some new futex tests rely on kernel features that may not be supported
on all configurations (e.g., FUTEX2_NUMA or PR_FUTEX_HASH).
Currently, thes

selftests/futex: Dynamically skip unsupported tests

Some new futex tests rely on kernel features that may not be supported
on all configurations (e.g., FUTEX2_NUMA or PR_FUTEX_HASH).
Currently, these tests fail with EINVAL when the features are missing.

Add dynamic skip logic to:

- futex_priv_hash: Skip if PR_FUTEX_HASH returns ENOSYS or EINVAL.

- futex_numa_mpol: Skip if futex2 or FUTEX2_NUMA returns ENOSYS or EINVAL.

This allows the tests to pass (as SKIPPED) on kernels without support,
while preserving coverage on configurations that do support them.

[ tglx: Adapt to harness changes, massage change log ]

Signed-off-by: Wake Liu <wakel@google.com>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Link: https://patch.msgid.link/20260624070223.1533167-1-wakel@google.com

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selftests/futex: Add FUTEX_LOCK_PI owner-exiting coverage

The futex functional tests cover FUTEX_LOCK_PI timeout semantics
(futex_wait_timeout.c) and robust-list owner death (robust_list.c), but
not

selftests/futex: Add FUTEX_LOCK_PI owner-exiting coverage

The futex functional tests cover FUTEX_LOCK_PI timeout semantics
(futex_wait_timeout.c) and robust-list owner death (robust_list.c), but
nothing exercises a non-robust PI owner exiting while holding the lock,
nor the basic ownership / EDEADLK / unlock word semantics of
FUTEX_LOCK_PI.

Add futex_lock_pi_exiting.c with three tests:

- lock_unlock_basic: an uncontended FUTEX_LOCK_PI puts the owner TID in
the futex word, a recursive lock by the owner returns EDEADLK, and
FUTEX_UNLOCK_PI clears the word.

- owner_dies_with_blocked_waiter: a thread acquires a PI futex and exits
while holding it; a blocked FUTEX_LOCK_PI waiter must come out cleanly
(0, EOWNERDEAD or ESRCH) and own the lock when it acquires.

- stress_owner_exits: repeatedly drive the same exiting-owner path.

The exiting-owner retry path is where commit 210d36d892de ("futex: Clear
stale exiting pointer in futex_lock_pi() retry path") fixed a stale task
pointer that tripped WARN_ON_ONCE() in wait_for_owner_exiting(). That
warning does not change the syscall return value, so this test does not
assert on it directly; the stress loop exists to give a kernel booted
with panic_on_warn=1 (as fuzzers and CI commonly run) a chance to trip
on it.

Signed-off-by: Valery Borovsky <vebohr@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Link: https://patch.msgid.link/20260607183249.246037-1-vebohr@gmail.com

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selftests/futex: Migrate robust_list to harness

Migrate robust_list test to the kselftest harness framework, removing mixed
legacy ksft_* API usages and passing test metadata to cloned child
functio

selftests/futex: Migrate robust_list to harness

Migrate robust_list test to the kselftest harness framework, removing mixed
legacy ksft_* API usages and passing test metadata to cloned child
functions via child_args struct.

Also, fix an out-of-bounds waitpid bug during multithreaded tests.

[ tglx: Fixup coding style ]

Signed-off-by: Wake Liu <wakel@google.com>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Link: https://patch.msgid.link/20260601065126.3623867-8-wakel@google.com

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selftests/futex: Migrate futex_priv_hash to harness

Migrate futex_priv_hash test to the kselftest harness framework, removing
mixed legacy ksft_* API usages and passing test metadata to all helper
f

selftests/futex: Migrate futex_priv_hash to harness

Migrate futex_priv_hash test to the kselftest harness framework, removing
mixed legacy ksft_* API usages and passing test metadata to all helper
functions.

[ tglx: Fixup coding style ]

Signed-off-by: Wake Liu <wakel@google.com>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Link: https://patch.msgid.link/20260601065126.3623867-7-wakel@google.com

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selftests/futex: Migrate futex_numa_mpol to harness

Migrate futex_numa_mpol test to the kselftest harness framework, removing
mixed legacy ksft_* API usages and passing test metadata to helper
funct

selftests/futex: Migrate futex_numa_mpol to harness

Migrate futex_numa_mpol test to the kselftest harness framework, removing
mixed legacy ksft_* API usages and passing test metadata to helper
functions.

[ tglx: Fixup coding style ]

Signed-off-by: Wake Liu <wakel@google.com>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Link: https://patch.msgid.link/20260601065126.3623867-6-wakel@google.com

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selftests/futex: Migrate futex_requeue_pi_signal_restart to harness

Migrate futex_requeue_pi_signal_restart test to the kselftest harness
framework, removing mixed legacy ksft_* API usages and ensur

selftests/futex: Migrate futex_requeue_pi_signal_restart to harness

Migrate futex_requeue_pi_signal_restart test to the kselftest harness
framework, removing mixed legacy ksft_* API usages and ensuring proper
thread joining.

[ tglx: Fixup coding style ]

Signed-off-by: Wake Liu <wakel@google.com>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Link: https://patch.msgid.link/20260601065126.3623867-5-wakel@google.com

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selftests/futex: Migrate futex_requeue_pi_mismatched_ops to harness

Migrate futex_requeue_pi_mismatched_ops test to the kselftest harness
framework, removing mixed legacy ksft_* API usages and passi

selftests/futex: Migrate futex_requeue_pi_mismatched_ops to harness

Migrate futex_requeue_pi_mismatched_ops test to the kselftest harness
framework, removing mixed legacy ksft_* API usages and passing test
metadata to helper thread.

[ tglx: Fixup coding style ]

Signed-off-by: Wake Liu <wakel@google.com>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Link: https://patch.msgid.link/20260601065126.3623867-4-wakel@google.com

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selftests/futex: Migrate futex_requeue_pi to harness

Migrate futex_requeue_pi test to the kselftest harness framework, removing
mixed legacy ksft_* API usages and passing test metadata to all helper

selftests/futex: Migrate futex_requeue_pi to harness

Migrate futex_requeue_pi test to the kselftest harness framework, removing
mixed legacy ksft_* API usages and passing test metadata to all helper
threads via thread arguments.

[ tglx: Fixup coding style ]

Signed-off-by: Wake Liu <wakel@google.com>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Link: https://patch.msgid.link/20260601065126.3623867-3-wakel@google.com

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selftests/futex: Migrate futex_requeue to harness

Migrate futex_requeue test to the kselftest harness framework, removing
mixed legacy ksft_* API usages and ensuring proper thread joining.

[ tglx:

selftests/futex: Migrate futex_requeue to harness

Migrate futex_requeue test to the kselftest harness framework, removing
mixed legacy ksft_* API usages and ensuring proper thread joining.

[ tglx: Fixup coding style ]

Signed-off-by: Wake Liu <wakel@google.com>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Link: https://patch.msgid.link/20260601065126.3623867-2-wakel@google.com

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selftests/futex: Migrate futex_wait_uninitialized_heap to harness

Migrate futex_wait_uninitialized_heap test to the kselftest harness
framework, removing mixed legacy ksft_* API usages and ensuring

selftests/futex: Migrate futex_wait_uninitialized_heap to harness

Migrate futex_wait_uninitialized_heap test to the kselftest harness
framework, removing mixed legacy ksft_* API usages and ensuring proper
thread joining.

[ tglx: Fixup coding style ]

Signed-off-by: Wake Liu <wakel@google.com>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Link: https://patch.msgid.link/20260525092002.3762888-4-wakel@google.com

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selftests/futex: Migrate futex_wait_private_mapped_file to harness

Migrate futex_wait_private_mapped_file test to the kselftest harness
framework, removing mixed legacy ksft_* API usages and passing

selftests/futex: Migrate futex_wait_private_mapped_file to harness

Migrate futex_wait_private_mapped_file test to the kselftest harness
framework, removing mixed legacy ksft_* API usages and passing test
metadata to helper thread.

[ tglx: Fixup coding style ]

Signed-off-by: Wake Liu <wakel@google.com>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Link: https://patch.msgid.link/20260525092002.3762888-3-wakel@google.com

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selftests/futex: Migrate futex_wait to harness

Migrate futex_wait test to the kselftest harness framework, removing mixed
legacy ksft_* API usages and ensuring proper thread joining.

[ tglx: Fixup

selftests/futex: Migrate futex_wait to harness

Migrate futex_wait test to the kselftest harness framework, removing mixed
legacy ksft_* API usages and ensuring proper thread joining.

[ tglx: Fixup coding style ]

Signed-off-by: Wake Liu <wakel@google.com>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Link: https://patch.msgid.link/20260525092002.3762888-2-wakel@google.com

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selftests/futex: Correct validation logic in waitv

In futex_waitv negative tests (invalid_flag, unaligned_address, etc.), test
results are evaluated as:

if (res == EINVAL)

Since sys_futex_waitv r

selftests/futex: Correct validation logic in waitv

In futex_waitv negative tests (invalid_flag, unaligned_address, etc.), test
results are evaluated as:

if (res == EINVAL)

Since sys_futex_waitv returns -1 on error and sets errno, direct positive
comparisons against res are always false, causing tests to silently pass
regardless of real errors.

Correct these validations to assert EXPECT_EQ(res, -1) and compare errno
directly against expected constants.

[ tglx: Fixup coding style ]

Signed-off-by: Wake Liu <wakel@google.com>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Link: https://patch.msgid.link/20260526010635.23980-3-wakel@google.com

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selftests/futex: Migrate functional tests to harness

Currently, multiple futex functional tests (wait_timeout, waitv,
wait_wouldblock) mix low-level ksft_* logging and result APIs with the
kselftest

selftests/futex: Migrate functional tests to harness

Currently, multiple futex functional tests (wait_timeout, waitv,
wait_wouldblock) mix low-level ksft_* logging and result APIs with the
kselftest_harness.h framework. On older kernels where system calls like
futex_waitv are missing (returning -ENOSYS), this mixed usage triggers
framework inconsistencies, causing the test to fail with: "Illegal usage of
low-level ksft APIs in harness test".

Address this by completely refactoring these tests to exclusively use
the high-level kselftest_harness.h framework (gtest-like API), mapping
all low-level calls to native harness macros:

- Non-fatal assertions: Replace ksft_test_result_fail() with EXPECT_EQ()
and EXPECT_NE().

- Fatal assertions: Replace ksft_exit_fail_msg() with ASSERT_EQ() and
ASSERT_TRUE() to immediately terminate execution upon setup failure.

- Test skipping: Replace ksft_exit_skip() with the graceful SKIP() macro
combined with early runtime availability checks for sys_futex_waitv.

- Debug logging: Replace ksft_print_dbg_msg() with TH_LOG() to inherit
automatic file/line context.

- Success reporting: Remove explicit ksft_test_result_pass() calls,
deferring to automated harness completion reporting.

Additionally:

- Fix a critical SIGSEGV crash in early syscall probing logic caused by
passing a NULL pointer to inline user-space timespec conversions.

- Introduce TEST_TIMEOUT() and GET_ABS_TIMEOUT() macros in wait_timeout
to encapsulate assertions while preserving source line attribution.

- Pass test metadata (_metadata) into secondary threads to allow native
harness assertions during concurrent execution.

[ tglx: Fixup coding style ]

Signed-off-by: Wake Liu <wakel@google.com>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Link: https://patch.msgid.link/20260526010635.23980-2-wakel@google.com

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selftests/futex: Remove static keyword from 'head'

'head' is defined as 'static struct robust_list_head' that stores the
local variable of 'struct lock_struct a' raising the Wdangling-pointer
warnin

selftests/futex: Remove static keyword from 'head'

'head' is defined as 'static struct robust_list_head' that stores the
local variable of 'struct lock_struct a' raising the Wdangling-pointer
warning.

robust_list.c: In function ‘child_circular_list’:
robust_list.c:522:24: warning: storing the address of local variable
‘a’ in ‘head.list.next’ [-Wdangling-pointer=]

522 | head.list.next = &a.list;
| ~~~~~~~~~~~~~~~^~~~~~~~~
robust_list.c:513:28: note: ‘a’ declared here
513 | struct lock_struct a, b, c;
| ^
robust_list.c:512:40: note: ‘head’ declared here
512 | static struct robust_list_head head;
| ^~~~

Since 'head' doesn't need static storge duration, removing the static
keyword of it to fix this.

Signed-off-by: Ankit Khushwaha <ankitkhushwaha.linux@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Link: https://patch.msgid.link/20260420173544.55288-1-ankitkhushwaha.linux@gmail.com

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