libbpf: Unpin auto-pinned maps if loading fails (ec6d5f47) · Commits · 戴 / test

Since the automatic map-pinning happens during load, it will leave pinned maps around if the load fails at a later stage. Fix this by unpinning any pinned maps on cleanup. To avoid unpinning pinned maps that were reused rather than newly pinned, add a new boolean property on struct bpf_map to keep track of whether that map was reused or not; and only unpin those maps that were not reused. Fixes: ("libbpf: Add auto-pinning of maps when loading BPF objects") Signed-off-by:

Toke Høiland-Jørgensen <toke@redhat.com> Signed-off-by:

Alexei Starovoitov <ast@kernel.org> Acked-by:

Andrii Nakryiko <andriin@fb.com> Acked-by:

David S. Miller <davem@davemloft.net> Acked-by:

Song Liu <songliubraving@fb.com> Link: https://lore.kernel.org/bpf/157333184731.88376.9992935027056165873.stgit@toke.dk

tools/lib/bpf/libbpf.c

+8 −1

Original line number	Diff line number	Diff line
		@@ -229,6 +229,7 @@ struct bpf_map {
		enum libbpf_map_type libbpf_type;
		char *pin_path;
		bool pinned;
		bool reused;
		};

		struct bpf_secdata {
		@@ -1995,6 +1996,7 @@ int bpf_map__reuse_fd(struct bpf_map *map, int fd)
		map->def.map_flags = info.map_flags;
		map->btf_key_type_id = info.btf_key_type_id;
		map->btf_value_type_id = info.btf_value_type_id;
		map->reused = true;

		return 0;

		@@ -4026,7 +4028,7 @@ int bpf_object__unload(struct bpf_object *obj)
		int bpf_object__load_xattr(struct bpf_object_load_attr *attr)
		{
		struct bpf_object *obj;
		int err;
		int err, i;

		if (!attr)
		return -EINVAL;
		@@ -4047,6 +4049,11 @@ int bpf_object__load_xattr(struct bpf_object_load_attr *attr)

		return 0;
		out:
		/* unpin any maps that were auto-pinned during load */
		for (i = 0; i < obj->nr_maps; i++)
		if (obj->maps[i].pinned && !obj->maps[i].reused)
		bpf_map__unpin(&obj->maps[i], NULL);

		bpf_object__unload(obj);
		pr_warn("failed to load object '%s'\n", obj->path);
		return err;

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