diff options
Diffstat (limited to 'kernel/trace/trace_kprobe.c')
| -rw-r--r-- | kernel/trace/trace_kprobe.c | 27 |
1 files changed, 20 insertions, 7 deletions
diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index 93507330462c..23f7f0ec4f4c 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -163,7 +163,8 @@ static bool trace_kprobe_match(const char *system, const char *event, { struct trace_kprobe *tk = to_trace_kprobe(ev); - return strcmp(trace_probe_name(&tk->tp), event) == 0 && + return (event[0] == '\0' || + strcmp(trace_probe_name(&tk->tp), event) == 0) && (!system || strcmp(trace_probe_group_name(&tk->tp), system) == 0) && trace_kprobe_match_command_head(tk, argc, argv); } @@ -708,11 +709,11 @@ static int __trace_kprobe_create(int argc, const char *argv[]) /* * Argument syntax: * - Add kprobe: - * p[:[GRP/]EVENT] [MOD:]KSYM[+OFFS]|KADDR [FETCHARGS] + * p[:[GRP/][EVENT]] [MOD:]KSYM[+OFFS]|KADDR [FETCHARGS] * - Add kretprobe: - * r[MAXACTIVE][:[GRP/]EVENT] [MOD:]KSYM[+0] [FETCHARGS] + * r[MAXACTIVE][:[GRP/][EVENT]] [MOD:]KSYM[+0] [FETCHARGS] * Or - * p:[GRP/]EVENT] [MOD:]KSYM[+0]%return [FETCHARGS] + * p[:[GRP/][EVENT]] [MOD:]KSYM[+0]%return [FETCHARGS] * * Fetch args: * $retval : fetch return value @@ -739,6 +740,7 @@ static int __trace_kprobe_create(int argc, const char *argv[]) long offset = 0; void *addr = NULL; char buf[MAX_EVENT_NAME_LEN]; + char gbuf[MAX_EVENT_NAME_LEN]; unsigned int flags = TPARG_FL_KERNEL; switch (argv[0][0]) { @@ -833,11 +835,13 @@ static int __trace_kprobe_create(int argc, const char *argv[]) trace_probe_log_set_index(0); if (event) { - ret = traceprobe_parse_event_name(&event, &group, buf, + ret = traceprobe_parse_event_name(&event, &group, gbuf, event - argv[0]); if (ret) goto parse_error; - } else { + } + + if (!event) { /* Make a new event name */ if (symbol) snprintf(buf, MAX_EVENT_NAME_LEN, "%c_%s_%ld", @@ -1718,8 +1722,17 @@ static int kretprobe_dispatcher(struct kretprobe_instance *ri, struct pt_regs *regs) { struct kretprobe *rp = get_kretprobe(ri); - struct trace_kprobe *tk = container_of(rp, struct trace_kprobe, rp); + struct trace_kprobe *tk; + + /* + * There is a small chance that get_kretprobe(ri) returns NULL when + * the kretprobe is unregister on another CPU between kretprobe's + * trampoline_handler and this function. + */ + if (unlikely(!rp)) + return 0; + tk = container_of(rp, struct trace_kprobe, rp); raw_cpu_inc(*tk->nhit); if (trace_probe_test_flag(&tk->tp, TP_FLAG_TRACE)) |