On Thu, Dec 9, 2021 at 7:05 PM Shuyi Cheng <chengshuyi@xxxxxxxxxxxxxxxxx> wrote: > > Fix error: "failed to pin map: Bad file descriptor, path: > /sys/fs/bpf/_rodata_str1_1." > > In the old kernel, the global data map will not be created, see [0]. So > we should skip the pinning of the global data map to avoid > bpf_object__pin_maps returning error. Therefore, when the map is not > created, we mark “map->skipped" as true and then check during relocation > and during pinning. > > Signed-off-by: Shuyi Cheng <chengshuyi@xxxxxxxxxxxxxxxxx> > --- This doesn't apply cleanly, can you please rebase on top of the latest bpf-next and resubmit? The changes themselves look good. > v1: > https://lore.kernel.org/bpf/CAEf4BzbtQGnGZTLbTdy1GHK54f5S7YNFQak7BuEfaqGEwqNNJA@xxxxxxxxxxxxxx/T/#m80ec7f8bc69dbcf4a5945e2aa6f16145901afc40 > v1->v2: > -- add "bool skipped" to struct bpf_map. > -- replace "bpf_map__is_internal(map) && !kernel_supports(obj, > FEAT_GLOBAL_DATA))" with map->skipped > > tools/lib/bpf/libbpf.c | 11 ++++++++--- > 1 file changed, 8 insertions(+), 3 deletions(-) > > diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c > index 18d95c6a89fe..a5bad6b43c15 100644 > --- a/tools/lib/bpf/libbpf.c > +++ b/tools/lib/bpf/libbpf.c > @@ -432,6 +432,7 @@ struct bpf_map { > bool pinned; > bool reused; > __u64 map_extra; > + bool skipped; please move up after pinned and reused to improve padding usage, thanks > }; > > enum extern_type { > @@ -5087,8 +5088,10 @@ bpf_object__create_maps(struct bpf_object *obj) > * kernels. > */ > if (bpf_map__is_internal(map) && > - !kernel_supports(obj, FEAT_GLOBAL_DATA)) > + !kernel_supports(obj, FEAT_GLOBAL_DATA)) { > + map->skipped = true; > continue; > + } > > retried = false; > retry: > @@ -5717,8 +5720,7 @@ bpf_object__relocate_data(struct bpf_object *obj, > struct bpf_program *prog) > } else { > const struct bpf_map *map = &obj->maps[relo->map_idx]; > > - if (bpf_map__is_internal(map) && > - !kernel_supports(obj, FEAT_GLOBAL_DATA)) { > + if (map->skipped) { > pr_warn("prog '%s': relo #%d: kernel doesn't support global data\n", > prog->name, i); > return -ENOTSUP; > @@ -7926,6 +7928,9 @@ int bpf_object__pin_maps(struct bpf_object *obj, > const char *path) > char *pin_path = NULL; > char buf[PATH_MAX]; > > + if (map->skipped) > + continue; > + > if (path) { > int len; > > -- > 2.19.1.6.gb485710b >
