On 10/07, Andrii Nakryiko wrote:
> As part of libbpf in 5e61f2707029 ("libbpf: stop enforcing kern_version,
> populate it for users") non-LIBBPF_API __bpf_object__open_xattr() API
> was removed from libbpf.h header. This broke bpftool, which relied on
> that function. This patch fixes the build by switching to newly added
> bpf_object__open_file() which provides the same capabilities, but is
> official and future-proof API.
>
> Fixes: 5e61f2707029 ("libbpf: stop enforcing kern_version, populate it for
> users")
> Reported-by: Stanislav Fomichev <s...@google.com>
> Signed-off-by: Andrii Nakryiko <andr...@fb.com>
> ---
> tools/bpf/bpftool/main.c | 4 ++--
> tools/bpf/bpftool/main.h | 2 +-
> tools/bpf/bpftool/prog.c | 22 ++++++++++++----------
> 3 files changed, 15 insertions(+), 13 deletions(-)
>
> diff --git a/tools/bpf/bpftool/main.c b/tools/bpf/bpftool/main.c
> index 93d008687020..4764581ff9ea 100644
> --- a/tools/bpf/bpftool/main.c
> +++ b/tools/bpf/bpftool/main.c
> @@ -27,7 +27,7 @@ bool json_output;
> bool show_pinned;
> bool block_mount;
> bool verifier_logs;
> -int bpf_flags;
> +bool relaxed_maps;
> struct pinned_obj_table prog_table;
> struct pinned_obj_table map_table;
>
> @@ -396,7 +396,7 @@ int main(int argc, char **argv)
> show_pinned = true;
> break;
> case 'm':
> - bpf_flags = MAPS_RELAX_COMPAT;
> + relaxed_maps = true;
> break;
> case 'n':
> block_mount = true;
> diff --git a/tools/bpf/bpftool/main.h b/tools/bpf/bpftool/main.h
> index af9ad56c303a..2899095f8254 100644
> --- a/tools/bpf/bpftool/main.h
> +++ b/tools/bpf/bpftool/main.h
> @@ -94,7 +94,7 @@ extern bool json_output;
> extern bool show_pinned;
> extern bool block_mount;
> extern bool verifier_logs;
> -extern int bpf_flags;
> +extern bool relaxed_maps;
> extern struct pinned_obj_table prog_table;
> extern struct pinned_obj_table map_table;
>
> diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c
> index 43fdbbfe41bb..8191cd595963 100644
> --- a/tools/bpf/bpftool/prog.c
> +++ b/tools/bpf/bpftool/prog.c
> @@ -1092,9 +1092,7 @@ static int do_run(int argc, char **argv)
> static int load_with_options(int argc, char **argv, bool first_prog_only)
> {
> struct bpf_object_load_attr load_attr = { 0 };
> - struct bpf_object_open_attr open_attr = {
> - .prog_type = BPF_PROG_TYPE_UNSPEC,
> - };
> + enum bpf_prog_type prog_type = BPF_PROG_TYPE_UNSPEC;
> enum bpf_attach_type expected_attach_type;
> struct map_replace *map_replace = NULL;
> struct bpf_program *prog = NULL, *pos;
> @@ -1105,11 +1103,16 @@ static int load_with_options(int argc, char **argv,
> bool first_prog_only)
> const char *pinfile;
> unsigned int i, j;
> __u32 ifindex = 0;
> + const char *file;
> int idx, err;
>
> + LIBBPF_OPTS(bpf_object_open_opts, open_opts,
> + .relaxed_maps = relaxed_maps,
> + );
> +
> if (!REQ_ARGS(2))
> return -1;
> - open_attr.file = GET_ARG();
> + file = GET_ARG();
> pinfile = GET_ARG();
>
> while (argc) {
> @@ -1118,7 +1121,7 @@ static int load_with_options(int argc, char **argv,
> bool first_prog_only)
>
> NEXT_ARG();
>
> - if (open_attr.prog_type != BPF_PROG_TYPE_UNSPEC) {
> + if (prog_type != BPF_PROG_TYPE_UNSPEC) {
> p_err("program type already specified");
> goto err_free_reuse_maps;
> }
> @@ -1135,8 +1138,7 @@ static int load_with_options(int argc, char **argv,
> bool first_prog_only)
> strcat(type, *argv);
> strcat(type, "/");
>
> - err = libbpf_prog_type_by_name(type,
> - &open_attr.prog_type,
> + err = libbpf_prog_type_by_name(type, &prog_type,
> &expected_attach_type);
> free(type);
> if (err < 0)
> @@ -1224,16 +1226,16 @@ static int load_with_options(int argc, char **argv,
> bool first_prog_only)
>
> set_max_rlimit();
>
> - obj = __bpf_object__open_xattr(&open_attr, bpf_flags);
> + obj = bpf_object__open_file(file, &open_opts);
> if (IS_ERR_OR_NULL(obj)) {
> p_err("failed to open object file");
> goto err_free_reuse_maps;
> }
>
> bpf_object__for_each_program(pos, obj) {
> - enum bpf_prog_type prog_type = open_attr.prog_type;
> + enum bpf_prog_type prog_type = prog_type;
Are you sure it works that way?
$ cat tmp.c
#include <stdio.h>
int main()
{
int x = 1;
printf("outer x=%d\n", x);
{
int x = x;
printf("inner x=%d\n", x);
}
return 0;
}
$ gcc tmp.c && ./a.out
outer x=1
inner x=0
Other than that:
Reviewed-by: Stanislav Fomichev <s...@google.com>
>
> - if (open_attr.prog_type == BPF_PROG_TYPE_UNSPEC) {
> + if (prog_type == BPF_PROG_TYPE_UNSPEC) {
> const char *sec_name = bpf_program__title(pos, false);
>
> err = libbpf_prog_type_by_name(sec_name, &prog_type,
> --
> 2.17.1
>
