samples/bpf: fix kprobe attachment issue on x64 (34745aed) · Commits · 戴 / test

Commit ("syscalls/core, syscalls/x86: Rename struct pt_regs-based sys_*() to __x64_sys_*()") renamed a lot of syscall function sys_*() to __x64_sys_*(). This caused several kprobe based samples/bpf tests failing. This patch fixed the problem in bpf_load.c. For x86_64 architecture, function name __x64_sys_*() will be first used for kprobe event creation. If the creation is successful, it will be used. Otherwise, function name sys_*() will be used for kprobe event creation. Fixes: ("syscalls/core, syscalls/x86: Rename struct pt_regs-based sys_*() to __x64_sys_*()") Signed-off-by:

Yonghong Song <yhs@fb.com> Signed-off-by:

Alexei Starovoitov <ast@kernel.org>

samples/bpf/bpf_load.c

+26 −8

Original line number	Diff line number	Diff line
		@@ -145,6 +145,9 @@ static int load_and_attach(const char event, struct bpf_insn prog, int size)
		}

		if (is_kprobe \|\| is_kretprobe) {
		bool need_normal_check = true;
		const char *event_prefix = "";

		if (is_kprobe)
		event += 7;
		else
		@@ -158,6 +161,19 @@ static int load_and_attach(const char event, struct bpf_insn prog, int size)
		if (isdigit(*event))
		return populate_prog_array(event, fd);

		#ifdef __x86_64__
		if (strncmp(event, "sys_", 4) == 0) {
		snprintf(buf, sizeof(buf),
		"echo '%c:__x64_%s __x64_%s' >> /sys/kernel/debug/tracing/kprobe_events",
		is_kprobe ? 'p' : 'r', event, event);
		err = system(buf);
		if (err >= 0) {
		need_normal_check = false;
		event_prefix = "__x64_";
		}
		}
		#endif
		if (need_normal_check) {
		snprintf(buf, sizeof(buf),
		"echo '%c:%s %s' >> /sys/kernel/debug/tracing/kprobe_events",
		is_kprobe ? 'p' : 'r', event, event);
		@@ -167,9 +183,11 @@ static int load_and_attach(const char event, struct bpf_insn prog, int size)
		event, strerror(errno));
		return -1;
		}
		}

		strcpy(buf, DEBUGFS);
		strcat(buf, "events/kprobes/");
		strcat(buf, event_prefix);
		strcat(buf, event);
		strcat(buf, "/id");
		} else if (is_tracepoint) {

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