From edc21dc909c6c133a2727f063eadd7907af51f94 Mon Sep 17 00:00:00 2001 From: Yinjun Zhang Date: Tue, 8 Feb 2022 00:00:25 +0800 Subject: [PATCH] bpftool: Fix the error when lookup in no-btf maps MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit When reworking btf__get_from_id() in commit a19f93cfafdf the error handling when calling bpf_btf_get_fd_by_id() changed. Before the rework if bpf_btf_get_fd_by_id() failed the error would not be propagated to callers of btf__get_from_id(), after the rework it is. This lead to a change in behavior in print_key_value() that now prints an error when trying to lookup keys in maps with no btf available. Fix this by following the way used in dumping maps to allow to look up keys in no-btf maps, by which it decides whether and where to get the btf info according to the btf value type. Fixes: a19f93cfafdf ("libbpf: Add internal helper to load BTF data by FD") Signed-off-by: Yinjun Zhang Signed-off-by: Simon Horman Signed-off-by: Andrii Nakryiko Reviewed-by: Niklas Söderlund Acked-by: Jiri Olsa Link: https://lore.kernel.org/bpf/1644249625-22479-1-git-send-email-yinjun.zhang@corigine.com --- tools/bpf/bpftool/map.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/tools/bpf/bpftool/map.c b/tools/bpf/bpftool/map.c index c66a3c979b7a..7a341a472ea4 100644 --- a/tools/bpf/bpftool/map.c +++ b/tools/bpf/bpftool/map.c @@ -1054,11 +1054,9 @@ static void print_key_value(struct bpf_map_info *info, void *key, json_writer_t *btf_wtr; struct btf *btf; - btf = btf__load_from_kernel_by_id(info->btf_id); - if (libbpf_get_error(btf)) { - p_err("failed to get btf"); + btf = get_map_kv_btf(info); + if (libbpf_get_error(btf)) return; - } if (json_output) { print_entry_json(info, key, value, btf);