kernel/tools/testing/selftests/bpf/trace_helpers.c, branch linux-rolling-stable

selftests/bpf: Fix realloc size in bpf_get_addrs

2025-10-01T20:37:30Z

We will segfault once we call realloc in bpf_get_addrs due to wrong size argument. Fixes: 6302bdeb91df ("selftests/bpf: Add a kprobe_multi subtest to use addrs instead of syms") Signed-off-by: Jiri Olsa Signed-off-by: Alexei Starovoitov

selftests/bpf: add benchmark testing for kprobe-multi-all

2025-09-04T16:00:25Z

For now, the benchmark for kprobe-multi is single, which means there is only 1 function is hooked during testing. Add the testing "kprobe-multi-all", which will hook all the kernel functions during the benchmark. And the "kretprobe-multi-all" is added too. Signed-off-by: Menglong Dong Link: https://lore.kernel.org/r/20250904021011.14069-4-dongml2@chinatelecom.cn Signed-off-by: Alexei Starovoitov

selftests/bpf: skip recursive functions for kprobe_multi

2025-09-04T16:00:25Z

Some functions is recursive for the kprobe_multi and impact the benchmark results. So just skip them. Signed-off-by: Menglong Dong Link: https://lore.kernel.org/r/20250904021011.14069-3-dongml2@chinatelecom.cn Signed-off-by: Alexei Starovoitov

selftests/bpf: move get_ksyms and get_addrs to trace_helpers.c

2025-09-04T16:00:25Z

We need to get all the kernel function that can be traced sometimes, so we move the get_syms() and get_addrs() in kprobe_multi_test.c to trace_helpers.c and rename it to bpf_get_ksyms() and bpf_get_addrs(). Signed-off-by: Menglong Dong Link: https://lore.kernel.org/r/20250904021011.14069-2-dongml2@chinatelecom.cn Signed-off-by: Alexei Starovoitov

selftests/bpf: Fix compilation error in get_uprobe_offset()

2024-12-19T12:24:39Z

In get_uprobe_offset(), the call to procmap_query() use the constant PROCMAP_QUERY_VMA_EXECUTABLE, even if PROCMAP_QUERY is not defined. Define PROCMAP_QUERY_VMA_EXECUTABLE when PROCMAP_QUERY isn't. Fixes: 4e9e07603ecd ("selftests/bpf: make use of PROCMAP_QUERY ioctl if available") Signed-off-by: Jerome Marchand Signed-off-by: Daniel Borkmann Acked-by: Yonghong Song Link: https://lore.kernel.org/bpf/20241218175724.578884-1-jmarchan@redhat.com

selftests/bpf: Fix procmap_query()'s params mismatch and compilation warning

2024-09-04T18:52:44Z

When the PROCMAP_QUERY is not defined, a compilation error occurs due to the mismatch of the procmap_query()'s params, procmap_query() only be called in the file where the function is defined, modify the params so they can match. We get a warning when build samples/bpf: trace_helpers.c:252:5: warning: no previous prototype for ‘procmap_query’ [-Wmissing-prototypes] 252 | int procmap_query(int fd, const void *addr, __u32 query_flags, size_t *start, size_t *offset, int *flags) | ^~~~~~~~~~~~~ As this function is only used in the file, mark it as 'static'. Fixes: 4e9e07603ecd ("selftests/bpf: make use of PROCMAP_QUERY ioctl if available") Signed-off-by: Yuan Chen Link: https://lore.kernel.org/r/20240903012839.3178-1-chenyuan_fl@163.com Signed-off-by: Alexei Starovoitov

selftests/bpf: make use of PROCMAP_QUERY ioctl if available

2024-08-23T14:46:39Z

Instead of parsing text-based /proc//maps file, try to use PROCMAP_QUERY ioctl() to simplify and speed up data fetching. This logic is used to do uprobe file offset calculation, so any bugs in this logic would manifest as failing uprobe BPF selftests. This also serves as a simple demonstration of one of the intended uses. Signed-off-by: Andrii Nakryiko Acked-by: Jiri Olsa Link: https://lore.kernel.org/r/20240806230319.869734-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov

selftests/bpf: Ignore .llvm. suffix in kallsyms_find()

2024-06-04T19:49:44Z

I hit the following failure when running selftests with internal backported upstream kernel: test_ksyms:PASS:kallsyms_fopen 0 nsec test_ksyms:FAIL:ksym_find symbol 'bpf_link_fops' not found #123 ksyms:FAIL In /proc/kallsyms, we have $ cat /proc/kallsyms | grep bpf_link_fops ffffffff829f0cb0 d bpf_link_fops.llvm.12608678492448798416 The CONFIG_LTO_CLANG_THIN is enabled in the kernel which is responsible for bpf_link_fops.llvm.12608678492448798416 symbol name. In prog_tests/ksyms.c we have kallsyms_find("bpf_link_fops", &link_fops_addr) and kallsyms_find() compares "bpf_link_fops" with symbols in /proc/kallsyms in order to find the entry. With bpf_link_fops.llvm. in /proc/kallsyms, the kallsyms_find() failed. To fix the issue, in kallsyms_find(), if a symbol has suffix .llvm., that suffix will be ignored for comparison. This fixed the test failure. Signed-off-by: Yonghong Song Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20240604180034.1356016-1-yonghong.song@linux.dev

selftests/bpf: Add read_trace_pipe_iter function

2024-04-12T16:25:21Z

We have two printk tests reading trace_pipe in non blocking way, with the very same code. Moving that in new read_trace_pipe_iter function. Current read_trace_pipe is used from samples/bpf and needs to do blocking read and printf of the trace_pipe data, using new read_trace_pipe_iter to implement that. Both printk tests do early checks for the number of found messages and can bail earlier, but I did not find any speed difference w/o that condition, so I did not complicate the change more for that. Some of the samples/bpf programs use read_trace_pipe function, so I kept that interface untouched. I did not see any issues with affected samples/bpf programs other than there's slight change in read_trace_pipe output. The current code uses puts that adds new line after the printed string, so we would occasionally see extra new line. With this patch we read output per lines, so there's no need to use puts and we can use just printf instead without extra new line. Signed-off-by: Jiri Olsa Signed-off-by: Daniel Borkmann Acked-by: Yonghong Song Link: https://lore.kernel.org/bpf/20240410140952.292261-1-jolsa@kernel.org

selftests/bpf: Add {load,search}_kallsyms_custom_local()

2024-03-29T01:31:41Z

These two functions allow selftests to do loading/searching kallsyms based on their specific compare functions. Signed-off-by: Yonghong Song Link: https://lore.kernel.org/r/20240326041513.1199440-1-yonghong.song@linux.dev Signed-off-by: Alexei Starovoitov