[PATCH bpf-next 2/2] selftests/bpf: Remove filter for unsafe functions in kprobe_multi test
From: Jiri Olsa <jolsa@kernel.org>
Date: 2022-05-15 20:37:29
Also in:
bpf, lkml
Subsystem:
bpf [general] (safe dynamic programs and tools), bpf [selftests] (test runners & infrastructure), kernel selftest framework, the rest · Maintainers:
Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Eduard Zingerman, Kumar Kartikeya Dwivedi, Shuah Khan, Linus Torvalds
Removing filter for arch_cpu_idle and rcu_* functions. Attaching to them was causing RCU warnings [1]: [ 3.017540] WARNING: suspicious RCU usage ... [ 3.018363] kprobe_multi_link_handler+0x68/0x1c0 [ 3.018364] ? kprobe_multi_link_handler+0x3e/0x1c0 [ 3.018366] ? arch_cpu_idle_dead+0x10/0x10 [ 3.018367] ? arch_cpu_idle_dead+0x10/0x10 [ 3.018371] fprobe_handler.part.0+0xab/0x150 [ 3.018374] 0xffffffffa00080c8 [ 3.018393] ? arch_cpu_idle+0x5/0x10 [ 3.018398] arch_cpu_idle+0x5/0x10 [ 3.018399] default_idle_call+0x59/0x90 [ 3.018401] do_idle+0x1c3/0x1d0 With previous fix the functions causing that are no longer attachable. [1] https://lore.kernel.org/bpf/CAEf4BzYtXWvBWzmadhLGqwf8_e2sruK6999th6c=b=O0WLkHOA@mail.gmail.com/ (local) Signed-off-by: Jiri Olsa <jolsa@kernel.org> --- .../selftests/bpf/prog_tests/kprobe_multi_test.c | 10 ---------- 1 file changed, 10 deletions(-)
diff --git a/tools/testing/selftests/bpf/prog_tests/kprobe_multi_test.c b/tools/testing/selftests/bpf/prog_tests/kprobe_multi_test.c
index 586dc52d6fb9..8bb974c263c3 100644
--- a/tools/testing/selftests/bpf/prog_tests/kprobe_multi_test.c
+++ b/tools/testing/selftests/bpf/prog_tests/kprobe_multi_test.c@@ -354,16 +354,6 @@ static int get_syms(char ***symsp, size_t *cntp) continue; if (sscanf(buf, "%ms$*[^\n]\n", &name) != 1) continue; - /* - * We attach to almost all kernel functions and some of them - * will cause 'suspicious RCU usage' when fprobe is attached - * to them. Filter out the current culprits - arch_cpu_idle - * and rcu_* functions. - */ - if (!strcmp(name, "arch_cpu_idle")) - continue; - if (!strncmp(name, "rcu_", 4)) - continue; err = hashmap__add(map, name, NULL); if (err) { free(name);
--
2.35.3