From 30460c21ed40a10bf541c4e93ba5e80bb4aac5da Mon Sep 17 00:00:00 2001 From: "Masami Hiramatsu (Google)" Date: Tue, 6 Jun 2023 21:39:55 +0900 Subject: tracing/probes: Avoid setting TPARG_FL_FENTRY and TPARG_FL_RETURN When parsing a kprobe event, the return probe always sets both TPARG_FL_RETURN and TPARG_FL_FENTRY, but this is not useful because some fetchargs are only for return probe and some others only for function entry. Make it obviously mutual exclusive. Link: https://lore.kernel.org/all/168507468731.913472.11354553441385410734.stgit@mhiramat.roam.corp.google.com/ Signed-off-by: Masami Hiramatsu (Google) --- kernel/trace/trace_kprobe.c | 2 +- kernel/trace/trace_probe.h | 5 +++++ 2 files changed, 6 insertions(+), 1 deletion(-) (limited to 'kernel') diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index 59cda19a9033..867ffb7ee31d 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -825,7 +825,7 @@ static int __trace_kprobe_create(int argc, const char *argv[]) if (is_return) flags |= TPARG_FL_RETURN; ret = kprobe_on_func_entry(NULL, symbol, offset); - if (ret == 0) + if (ret == 0 && !is_return) flags |= TPARG_FL_FENTRY; /* Defer the ENOENT case until register kprobe */ if (ret == -EINVAL && is_return) { diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h index 6a4ecfb1da43..5df59714f9f5 100644 --- a/kernel/trace/trace_probe.h +++ b/kernel/trace/trace_probe.h @@ -357,6 +357,11 @@ int trace_probe_print_args(struct trace_seq *s, struct probe_arg *args, int nr_a #define trace_probe_for_each_link_rcu(pos, tp) \ list_for_each_entry_rcu(pos, &(tp)->event->files, list) +/* + * The flags used for parsing trace_probe arguments. + * TPARG_FL_RETURN, TPARG_FL_FENTRY and TPARG_FL_TPOINT are mutually exclusive. + * TPARG_FL_KERNEL and TPARG_FL_USER are also mutually exclusive. + */ #define TPARG_FL_RETURN BIT(0) #define TPARG_FL_KERNEL BIT(1) #define TPARG_FL_FENTRY BIT(2) -- cgit v1.2.3