After install the libelf-dev package and compiling perf, kptr_restrict=2 and perf_event_paranoid=3 will cause perf top to crash, because the value of /proc/kallsyms cannot be obtained, which leads to info->jited_ksyms == NULL. In order to solve this problem, Add a judgment before use.
Suggested-by: Jiri Olsa <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Arnaldo Carvalho de Melo <[email protected]> Cc: Mark Rutland <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: Namhyung Kim <[email protected]> Signed-off-by: Jackie Liu <[email protected]> --- tools/perf/util/bpf-event.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/tools/perf/util/bpf-event.c b/tools/perf/util/bpf-event.c index 57d58c81a5f8..b1ce2d189d37 100644 --- a/tools/perf/util/bpf-event.c +++ b/tools/perf/util/bpf-event.c @@ -225,6 +225,11 @@ static int perf_event__synthesize_one_bpf_prog(struct perf_session *session, perf_env__fetch_btf(env, info->btf_id, btf); } + if (!info->jited_ksyms) { + err = -1; + goto out; + } + /* Synthesize PERF_RECORD_KSYMBOL */ for (i = 0; i < sub_prog_cnt; i++) { __u32 *prog_lens = (__u32 *)(uintptr_t)(info->jited_func_lens); -- 2.25.1
