diff options
| author | Vincent Li <vincent.mc.li@gmail.com> | 2025-08-18 19:51:13 +0300 |
|---|---|---|
| committer | Daniel Borkmann <daniel@iogearbox.net> | 2025-08-19 11:13:38 +0300 |
| commit | bf7a6a67050f5d59a674ecc3ecd06d6b09cfec49 (patch) | |
| tree | 7b32dbe1449325e43188ae55847866ae05bce385 /tools/bpf/bpftool | |
| parent | 5c42715e63a3cd1c69107402aefa136e3a324fab (diff) | |
| download | linux-bf7a6a67050f5d59a674ecc3ecd06d6b09cfec49.tar.xz | |
bpftool: Add kernel.kptr_restrict hint for no instructions
From bpftool's github repository issue [0]: When a Linux distribution
has the kernel.kptr_restrict set to 2, bpftool prog dump jited returns
"no instructions returned". This message can be puzzling to bpftool
users who are not familiar with kernel BPF internals, so add a small
hint for bpftool users to check the kernel.kptr_restrict setting
similar to the DUMP_XLATED case. Outside of kernel.kptr_restrict, no
instructions could also be returned in case the JIT was disabled.
Signed-off-by: Vincent Li <vincent.mc.li@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://github.com/libbpf/bpftool/issues/184 [0]
Link: https://lore.kernel.org/bpf/20250818165113.15982-1-vincent.mc.li@gmail.com
Diffstat (limited to 'tools/bpf/bpftool')
| -rw-r--r-- | tools/bpf/bpftool/prog.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c index 9722d841abc0..cf18c3879680 100644 --- a/tools/bpf/bpftool/prog.c +++ b/tools/bpf/bpftool/prog.c @@ -714,7 +714,7 @@ prog_dump(struct bpf_prog_info *info, enum dump_mode mode, if (mode == DUMP_JITED) { if (info->jited_prog_len == 0 || !info->jited_prog_insns) { - p_info("no instructions returned"); + p_err("error retrieving jit dump: no instructions returned or kernel.kptr_restrict set?"); return -1; } buf = u64_to_ptr(info->jited_prog_insns); |