Kernel function urandom_read is replaced with urandom_read_iter. Therefore, kprobe on urandom_read is not working any more: [root@eth50-1 bpf]# ./test_progs -n 161 test_stacktrace_build_id:PASS:skel_open_and_load 0 nsec libbpf: kprobe perf_event_open() failed: No such file or directory libbpf: prog 'oncpu': failed to create kprobe 'urandom_read+0x0' \ perf event: No such file or directory libbpf: prog 'oncpu': failed to auto-attach: -2 test_stacktrace_build_id:FAIL:attach_tp err -2 161 stacktrace_build_id:FAIL Fix this by replacing urandom_read with urandom_read_iter in the test. Fixes: 1b388e7765f2 ("random: convert to using fops->read_iter()") Reported-by: Mykola Lysenko <mykolal@xxxxxx> Signed-off-by: Song Liu <song@xxxxxxxxxx> --- tools/testing/selftests/bpf/progs/test_stacktrace_build_id.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/testing/selftests/bpf/progs/test_stacktrace_build_id.c b/tools/testing/selftests/bpf/progs/test_stacktrace_build_id.c index 6c62bfb8bb6f..0c4426592a26 100644 --- a/tools/testing/selftests/bpf/progs/test_stacktrace_build_id.c +++ b/tools/testing/selftests/bpf/progs/test_stacktrace_build_id.c @@ -39,7 +39,7 @@ struct { __type(value, stack_trace_t); } stack_amap SEC(".maps"); -SEC("kprobe/urandom_read") +SEC("kprobe/urandom_read_iter") int oncpu(struct pt_regs *args) { __u32 max_len = sizeof(struct bpf_stack_build_id) -- 2.30.2