From: Jiri Olsa <jolsa@redhat.com>
To: Andrii Nakryiko <andrii.nakryiko@gmail.com>
Cc: Andrii Nakryiko <andrii@kernel.org>, bpf <bpf@vger.kernel.org>,
Networking <netdev@vger.kernel.org>,
Alexei Starovoitov <ast@fb.com>,
Daniel Borkmann <daniel@iogearbox.net>,
Kernel Team <kernel-team@fb.com>
Subject: Re: [PATCH v4 bpf-next 07/12] libbpf: add BPF static linker BTF and BTF.ext support
Date: Sun, 28 Mar 2021 14:03:38 +0200 [thread overview]
Message-ID: <YGBwmlQTDUodxM0J@krava> (raw)
In-Reply-To: <YFT0Q+mVbTEI1rem@krava>
On Fri, Mar 19, 2021 at 07:58:13PM +0100, Jiri Olsa wrote:
> On Fri, Mar 19, 2021 at 11:39:01AM -0700, Andrii Nakryiko wrote:
> > On Fri, Mar 19, 2021 at 9:23 AM Jiri Olsa <jolsa@redhat.com> wrote:
> > >
> > > On Thu, Mar 18, 2021 at 12:40:31PM -0700, Andrii Nakryiko wrote:
> > >
> > > SNIP
> > >
> > > > +
> > > > + return NULL;
> > > > +}
> > > > +
> > > > +static int linker_fixup_btf(struct src_obj *obj)
> > > > +{
> > > > + const char *sec_name;
> > > > + struct src_sec *sec;
> > > > + int i, j, n, m;
> > > > +
> > > > + n = btf__get_nr_types(obj->btf);
> > >
> > > hi,
> > > I'm getting bpftool crash when building tests,
> > >
> > > looks like above obj->btf can be NULL:
> >
> > I lost if (!obj->btf) return 0; somewhere along the rebases. I'll send
> > a fix shortly. But how did you end up with selftests BPF objects built
> > without BTF?
>
> no idea.. I haven't even updated llvm for almost 3 days now ;-)
sorry for late follow up on this, and it's actually forgotten empty
object in progs directory that was causing this
I wonder we should add empty object like below to catch these cases,
because there's another place that bpftool is crashing on with it
I can send full patch for that if you think it's worth having
jirka
---
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 7aad78dbb4b4..aecb6ca52bce 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -3165,6 +3165,9 @@ static int add_dummy_ksym_var(struct btf *btf)
const struct btf_var_secinfo *vs;
const struct btf_type *sec;
+ if (!btf)
+ return 0;
+
sec_btf_id = btf__find_by_name_kind(btf, KSYMS_SEC,
BTF_KIND_DATASEC);
if (sec_btf_id < 0)
diff --git a/tools/testing/selftests/bpf/progs/empty.c b/tools/testing/selftests/bpf/progs/empty.c
new file mode 100644
index 000000000000..e69de29bb2d1
next prev parent reply other threads:[~2021-03-28 12:09 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-03-18 19:40 [PATCH v4 bpf-next 00/12] BPF static linking Andrii Nakryiko
2021-03-18 19:40 ` [PATCH v4 bpf-next 01/12] libbpf: expose btf_type_by_id() internally Andrii Nakryiko
2021-03-18 19:40 ` [PATCH v4 bpf-next 02/12] libbpf: generalize BTF and BTF.ext type ID and strings iteration Andrii Nakryiko
2021-03-18 19:40 ` [PATCH v4 bpf-next 03/12] libbpf: rename internal memory-management helpers Andrii Nakryiko
2021-03-18 19:40 ` [PATCH v4 bpf-next 04/12] libbpf: extract internal set-of-strings datastructure APIs Andrii Nakryiko
2021-03-18 19:40 ` [PATCH v4 bpf-next 05/12] libbpf: add generic BTF type shallow copy API Andrii Nakryiko
2021-03-18 19:40 ` [PATCH v4 bpf-next 06/12] libbpf: add BPF static linker APIs Andrii Nakryiko
2021-03-18 19:40 ` [PATCH v4 bpf-next 07/12] libbpf: add BPF static linker BTF and BTF.ext support Andrii Nakryiko
2021-03-19 16:23 ` Jiri Olsa
2021-03-19 18:39 ` Andrii Nakryiko
2021-03-19 18:58 ` Jiri Olsa
2021-03-28 12:03 ` Jiri Olsa [this message]
2021-03-28 18:29 ` Andrii Nakryiko
2021-03-29 11:16 ` Jiri Olsa
2021-03-18 19:40 ` [PATCH v4 bpf-next 08/12] bpftool: add ability to specify custom skeleton object name Andrii Nakryiko
2021-03-18 19:40 ` [PATCH v4 bpf-next 09/12] bpftool: add `gen object` command to perform BPF static linking Andrii Nakryiko
2021-03-18 19:40 ` [PATCH v4 bpf-next 10/12] selftests/bpf: re-generate vmlinux.h and BPF skeletons if bpftool changed Andrii Nakryiko
2021-03-18 19:40 ` [PATCH v4 bpf-next 11/12] selftests/bpf: pass all BPF .o's through BPF static linker Andrii Nakryiko
2021-03-18 19:40 ` [PATCH v4 bpf-next 12/12] selftests/bpf: add multi-file statically linked BPF object file test Andrii Nakryiko
2021-03-18 23:29 ` [PATCH v4 bpf-next 00/12] BPF static linking Alexei Starovoitov
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=YGBwmlQTDUodxM0J@krava \
--to=jolsa@redhat.com \
--cc=andrii.nakryiko@gmail.com \
--cc=andrii@kernel.org \
--cc=ast@fb.com \
--cc=bpf@vger.kernel.org \
--cc=daniel@iogearbox.net \
--cc=kernel-team@fb.com \
--cc=netdev@vger.kernel.org \
--subject='Re: [PATCH v4 bpf-next 07/12] libbpf: add BPF static linker BTF and BTF.ext support' \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).