1BPFTOOL-FEATURE(8) BPFTOOL-FEATURE(8)
2
6 bpftool-feature - tool for inspection of eBPF-related parameters for
7 Linux kernel or net device
8
10 bpftool [OPTIONS] feature COMMAND
11 OPTIONS := { { -j | --json } [{ -p | --pretty }] }
13 COMMANDS := { probe | help }
15
17 bpftool feature probe [COMPONENT] [full] [unprivileged] [macros [prefix PREFIX]]
18 bpftool feature help
19 COMPONENT := { kernel | dev NAME }
21
24 bpftool feature probe [kernel] [full] [macros [prefix PREFIX]]
25 Probe the running kernel and dump a number of eBPF-related
26 parameters, such as availability of the bpf() system call,
27 JIT status, eBPF program types availability, eBPF helper
28 functions availability, and more.
29 By default, bpftool does not run probes for
31 bpf_probe_write_user() and bpf_trace_printk() helpers which
32 print warnings to kernel logs. To enable them and run all
33 probes, the full keyword should be used.
34 If the macros keyword (but not the -j option) is passed, a
36 subset of the output is dumped as a list of #define macros
37 that are ready to be included in a C header file, for exam‐
38 ple. If, additionally, prefix is used to define a PREFIX, the
39 provided string will be used as a prefix to the names of the
40 macros: this can be used to avoid conflicts on macro names
41 when including the output of this command as a header file.
42 Keyword kernel can be omitted. If no probe target is speci‐
44 fied, probing the kernel is the default behaviour.
45 When the unprivileged keyword is used, bpftool will dump only
47 the features available to a user who does not have the
48 CAP_SYS_ADMIN capability set. The features available in that
49 case usually represent a small subset of the parameters sup‐
50 ported by the system. Unprivileged users MUST use the unpriv‐
51 ileged keyword: This is to avoid misdetection if bpftool is
52 inadvertently run as non-root, for example. This keyword is
53 unavailable if bpftool was compiled without libcap.
54 bpftool feature probe dev NAME [full] [macros [prefix PREFIX]]
56 Probe network device for supported eBPF features and dump
57 results to the console.
58 The keywords full, macros and prefix have the same role as
60 when probing the kernel.
61 bpftool feature help
63 Print short help message.
64
66 -h, --help
67 Print short help message (similar to bpftool help).
68 -V, --version
70 Print version number (similar to bpftool version), and
71 optional features that were included when bpftool was com‐
72 piled. Optional features include linking against libbfd to
73 provide the disassembler for JIT-ted programs (bpftool prog
74 dump jited) and usage of BPF skeletons (some features like
75 bpftool prog profile or showing pids associated to BPF
76 objects may rely on it).
77 -j, --json
79 Generate JSON output. For commands that cannot produce JSON,
80 this option has no effect.
81 -p, --pretty
83 Generate human-readable JSON output. Implies -j.
84 -d, --debug
86 Print all logs available, even debug-level information. This
87 includes logs from libbpf as well as from the verifier, when
88 attempting to load programs.
89
91 bpf(2), bpf-helpers(7), bpftool(8), bpftool-btf(8),
92 bpftool-cgroup(8), bpftool-gen(8), bpftool-iter(8), bpftool-link(8),
93 bpftool-map(8), bpftool-net(8), bpftool-perf(8), bpftool-prog(8),
94 bpftool-struct_ops(8)
95 BPFTOOL-FEATURE(8)