kernel/linux.git/tools/testing/selftests/bpf/prog_tests/module_attach.c, branch linux-7.1.y

selftests/bpf: Speed up module_attach test

2026-03-11T16:29:09+00:00

The module_attach test contains subtests which check that unloading a module while there are BPF programs attached to its functions is not possible because the module is still referenced. The problem is that the test calls the generic unload_module() helper function which is used for module cleanup after test_progs terminate and tries to wait until all module references are released. This unnecessarily slows down the module_attach subtests since each unsuccessful call to unload_module() takes about 1 second. Introduce try_unload_module() which takes the number of retries as a parameter. Make unload_module() call it with the currently used amount of 10000 retries but call it with just 1 retry from module_attach tests as it is always expected to fail. This speeds up the module_attach() test significantly. Before: # time ./test_progs -t module_attach [...] Summary: 1/14 PASSED, 0 SKIPPED, 0 FAILED real 0m5.011s user 0m0.293s sys 0m0.108s After: # time ./test_progs -t module_attach [...] Summary: 1/14 PASSED, 0 SKIPPED, 0 FAILED real 0m0.350s user 0m0.197s sys 0m0.063s Signed-off-by: Viktor Malik Reviewed-by: Alan Maguire Tested-by: Alan Maguire Acked-by: Kumar Kartikeya Dwivedi Link: https://lore.kernel.org/r/20260306101628.3822284-1-vmalik@redhat.com Signed-off-by: Alexei Starovoitov

selftests/bpf: Split module_attach into subtests

2026-03-03T17:23:57+00:00

The test verifies attachment to various hooks in a kernel module, however, everything is flattened into a single test. This makes it impossible to run or skip test cases selectively. Isolate each BPF program into a separate subtest. This is done by disabling auto-loading of programs and loading and testing each program separately. At the same time, modernize the test to use ASSERT* instead of CHECK and replace `return` by `goto cleanup` where necessary. Signed-off-by: Viktor Malik Link: https://lore.kernel.org/r/20260225120904.1529112-1-vmalik@redhat.com Signed-off-by: Alexei Starovoitov

selftests/bpf: Fix typos and grammar in test sources

2025-08-27T22:13:08+00:00

Fix spelling typos and grammar errors in BPF selftests source code. Signed-off-by: Shubham Sharma Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20250826125746.17983-1-slopixelz@gmail.com

selftests/bpf: add tests for the "module: Function" syntax

2024-05-01T16:53:48+00:00

The previous patch added support for the "module:function" syntax for tracing programs. This adds tests for explicitly specifying the module name via the SEC macro and via the bpf_program__set_attach_target call. Signed-off-by: Viktor Malik Signed-off-by: Andrii Nakryiko Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/8a076168ed847f7c8a6c25715737b1fea84e38be.1714469650.git.vmalik@redhat.com

selftests/bpf: Use un/load_bpf_testmod functions in tests

2023-05-17T05:09:23+00:00

Now that we have un/load_bpf_testmod helpers in testing_helpers.h, we can use it in other tests and save some lines. Acked-by: David Vernet Signed-off-by: Jiri Olsa Link: https://lore.kernel.org/r/20230515133756.1658301-7-jolsa@kernel.org Signed-off-by: Alexei Starovoitov

selftests/bpf: Add kprobe_multi check to module attach test

2022-10-25T17:14:51+00:00

Adding test that makes sure the kernel module won't be removed if there's kprobe multi link defined on top of it. Acked-by: Song Liu Signed-off-by: Jiri Olsa Link: https://lore.kernel.org/r/20221025134148.3300700-8-jolsa@kernel.org Signed-off-by: Alexei Starovoitov

bpf/selftests: Add test for writable bare tracepoint

2021-10-08T20:22:57+00:00

Add a writable bare tracepoint in bpf_testmod module, and trigger its calling when reading /sys/kernel/bpf_testmod with a specific buffer length. The reading will return the value in writable context if the early return flag is enabled in writable context. Signed-off-by: Hou Tao Signed-off-by: Andrii Nakryiko Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20211004094857.30868-4-hotforest@gmail.com

selftests/bpf: Add test for bpf_get_branch_snapshot

2021-09-13T17:53:50+00:00

This test uses bpf_get_branch_snapshot from a fexit program. The test uses a target function (bpf_testmod_loop_test) and compares the record against kallsyms. If there isn't enough record matching kallsyms, the test fails. Signed-off-by: Song Liu Signed-off-by: Alexei Starovoitov Acked-by: Andrii Nakryiko Acked-by: John Fastabend Link: https://lore.kernel.org/bpf/20210910183352.3151445-4-songliubraving@fb.com

selftests/bpf: Test that module can't be unloaded with attached trampoline

2021-04-26T04:09:02+00:00

Adding test to verify that once we attach module's trampoline, the module can't be unloaded. Signed-off-by: Jiri Olsa Signed-off-by: Alexei Starovoitov Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20210414195147.1624932-7-jolsa@kernel.org

selftests: bpf: Add a new test for bare tracepoints

2021-01-20T22:14:05+00:00

Reuse module_attach infrastructure to add a new bare tracepoint to check we can attach to it as a raw tracepoint. Signed-off-by: Qais Yousef Signed-off-by: Alexei Starovoitov Acked-by: Yonghong Song Link: https://lore.kernel.org/bpf/20210119122237.2426878-3-qais.yousef@arm.com