kernel.git/tools/testing/selftests/bpf/prog_tests/log_buf.c, branch master

selftests/bpf: Fix RELEASE build failure with gcc14

2025-06-17T17:18:30Z

With gcc14, when building with RELEASE=1, I hit four below compilation failure: Error 1: In file included from test_loader.c:6: test_loader.c: In function ‘run_subtest’: test_progs.h:194:17: error: ‘retval’ may be used uninitialized in this function [-Werror=maybe-uninitialized] 194 | fprintf(stdout, ##format); \ | ^~~~~~~ test_loader.c:958:13: note: ‘retval’ was declared here 958 | int retval, err, i; | ^~~~~~ The uninitialized var 'retval' actually could cause incorrect result. Error 2: In function ‘test_fd_array_cnt’: prog_tests/fd_array.c:71:14: error: ‘btf_id’ may be used uninitialized in this function [-Werror=maybe-uninitialized] 71 | fd = bpf_btf_get_fd_by_id(id); | ^~~~~~~~~~~~~~~~~~~~~~~~ prog_tests/fd_array.c:302:15: note: ‘btf_id’ was declared here 302 | __u32 btf_id; | ^~~~~~ Changing ASSERT_GE to ASSERT_EQ can fix the compilation error. Otherwise, there is no functionality change. Error 3: prog_tests/tailcalls.c: In function ‘test_tailcall_hierarchy_count’: prog_tests/tailcalls.c:1402:23: error: ‘fentry_data_fd’ may be used uninitialized in this function [-Werror=maybe-uninitialized] 1402 | err = bpf_map_lookup_elem(fentry_data_fd, &i, &val); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ The code is correct. The change intends to silence gcc errors. Error 4: (this error only happens on arm64) In file included from prog_tests/log_buf.c:4: prog_tests/log_buf.c: In function ‘bpf_prog_load_log_buf’: ./test_progs.h:390:22: error: ‘log_buf’ may be used uninitialized [-Werror=maybe-uninitialized] 390 | int ___err = libbpf_get_error(___res); \ | ^~~~~~~~~~~~~~~~~~~~~~~~ prog_tests/log_buf.c:158:14: note: in expansion of macro ‘ASSERT_OK_PTR’ 158 | if (!ASSERT_OK_PTR(log_buf, "log_buf_alloc")) | ^~~~~~~~~~~~~ In file included from selftests/bpf/tools/include/bpf/bpf.h:32, from ./test_progs.h:36: selftests/bpf/tools/include/bpf/libbpf_legacy.h:113:17: note: by argument 1 of type ‘const void *’ to ‘libbpf_get_error’ declared here 113 | LIBBPF_API long libbpf_get_error(const void *ptr); | ^~~~~~~~~~~~~~~~ Adding a pragma to disable maybe-uninitialized fixed the issue. Signed-off-by: Yonghong Song Link: https://lore.kernel.org/r/20250617044956.2686668-1-yonghong.song@linux.dev Signed-off-by: Alexei Starovoitov

selftests/bpf: Removed redundant fd after close in bpf_prog_load_log_buf

2024-10-11T02:15:02Z

Removed unnecessary `fd = -1` assignments after closing file descriptors. because it will be assigned by the function bpf_prog_load().This improves code readability and removes redundant operations. Signed-off-by: Zhu Jun Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20241010055737.4292-1-zhujun2@cmss.chinamobile.com

selftests/bpf: fix some typos in selftests

2024-09-05T20:07:47Z

Hi, fix some spelling errors in selftest, the details are as follows: -in the codes: test_bpf_sk_stoarge_map_iter_fd(void) ->test_bpf_sk_storage_map_iter_fd(void) load BTF from btf_data.o->load BTF from btf_data.bpf.o -in the code comments: preample->preamble multi-contollers->multi-controllers errono->errno unsighed/unsinged->unsigned egree->egress shoud->should regsiter->register assummed->assumed conditiona->conditional rougly->roughly timetamp->timestamp ingores->ignores null-termainted->null-terminated slepable->sleepable implemenation->implementation veriables->variables timetamps->timestamps substitue a costant->substitute a constant secton->section unreferened->unreferenced verifer->verifier libppf->libbpf ... Signed-off-by: Lin Yikai Link: https://lore.kernel.org/r/20240905110354.3274546-1-yikai.lin@vivo.com Signed-off-by: Alexei Starovoitov

selftests: bpf: Replace sizeof(arr)/sizeof(arr[0]) with ARRAY_SIZE

2024-09-04T19:58:46Z

The ARRAY_SIZE macro is more compact and more formal in linux source. Signed-off-by: Feng Yang Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20240903072559.292607-1-yangfeng59949@163.com

bpf: omit default off=0 and imm=0 in register state log

2023-11-18T19:39:59Z

Simplify BPF verifier log further by omitting default (and frequently irrelevant) off=0 and imm=0 parts for non-SCALAR_VALUE registers. As can be seen from fixed tests, this is often a visual noise for PTR_TO_CTX register and even for PTR_TO_PACKET registers. Omitting default values follows the rest of register state logic: we omit default values to keep verifier log succinct and to highlight interesting state that deviates from default one. E.g., we do the same for var_off, when it's unknown, which gives no additional information. Acked-by: Eduard Zingerman Acked-by: Stanislav Fomichev Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/r/20231118034623.3320920-7-andrii@kernel.org Signed-off-by: Alexei Starovoitov

bpf: Small BPF verifier log improvements

2022-03-03T15:54:10Z

In particular these include: 1) Remove output of inv for scalars in print_verifier_state 2) Replace inv with scalar in verifier error messages 3) Remove _value suffixes for umin/umax/s32_min/etc (except map_value) 4) Remove output of id=0 5) Remove output of ref_obj_id=0 Signed-off-by: Mykola Lysenko Signed-off-by: Daniel Borkmann Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20220301222745.1667206-1-mykolal@fb.com

selftests/bpf: Fix a clang compilation error

2022-01-26T20:07:01Z

Compiling kernel and selftests/bpf with latest llvm like blow: make -j LLVM=1 make -C tools/testing/selftests/bpf -j LLVM=1 I hit the following compilation error: /.../prog_tests/log_buf.c:215:6: error: variable 'log_buf' is used uninitialized whenever 'if' condition is true [-Werror,-Wsometimes-uninitialized] if (!ASSERT_OK_PTR(raw_btf_data, "raw_btf_data_good")) ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ /.../prog_tests/log_buf.c:264:7: note: uninitialized use occurs here free(log_buf); ^~~~~~~ /.../prog_tests/log_buf.c:215:2: note: remove the 'if' if its condition is always false if (!ASSERT_OK_PTR(raw_btf_data, "raw_btf_data_good")) ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ /.../prog_tests/log_buf.c:205:15: note: initialize the variable 'log_buf' to silence this warning char *log_buf; ^ = NULL 1 error generated. Compiler rightfully detected that log_buf is uninitialized in one of failure path as indicated in the above. Proper initialization of 'log_buf' variable fixed the issue. Signed-off-by: Yonghong Song Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20220126181940.4105997-1-yhs@fb.com

selftests/bpf: Add test for libbpf's custom log_buf behavior

2021-12-10T23:29:18Z

Add a selftest that validates that per-program and per-object log_buf overrides work as expected. Also test same logic for low-level bpf_prog_load() and bpf_btf_load() APIs. Signed-off-by: Andrii Nakryiko Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20211209193840.1248570-11-andrii@kernel.org