From: Alexei Starovoitov <alexei.starovoitov@gmail.com>
To: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Cc: "Andrii Nakryiko" <andrii.nakryiko@gmail.com>,
bpf <bpf@vger.kernel.org>, "Alexei Starovoitov" <ast@kernel.org>,
"Daniel Borkmann" <daniel@iogearbox.net>,
"Andrii Nakryiko" <andrii@kernel.org>,
"Martin KaFai Lau" <kafai@fb.com>,
"Song Liu" <songliubraving@fb.com>, "Yonghong Song" <yhs@fb.com>,
"Jesper Dangaard Brouer" <brouer@redhat.com>,
"Toke Høiland-Jørgensen" <toke@redhat.com>,
Networking <netdev@vger.kernel.org>
Subject: Re: [PATCH bpf-next v4 11/11] bpf: selftests: Add selftests for module kfunc support
Date: Wed, 22 Sep 2021 11:24:15 -0700 [thread overview]
Message-ID: <CAADnVQJb_mwxNRBdqaE_E=05V=YVHt5wrxSMigSYRMNvv4LWZg@mail.gmail.com> (raw)
In-Reply-To: <20210922060608.fxdaeguiako4oixb@apollo.localdomain>
On Tue, Sep 21, 2021 at 11:06 PM Kumar Kartikeya Dwivedi
<memxor@gmail.com> wrote:
>
> On Wed, Sep 22, 2021 at 05:33:26AM IST, Andrii Nakryiko wrote:
> > > [...]
> > > Hmm, good idea, I'd just need to fill in the BTF id dynamically at runtime,
> > > but that should be possible.
> > >
> > > Though we still need to craft distinct calls (I am trying to test the limit
> > > where insn->off is different for each case). Since we try to reuse index in both
> > > gen_loader and libbpf, just generating same call 256 times would not be enough.
> >
> > You just need to generate one instruction with offset = 257 to test
> > this. And separately one call with fd_array that has module BTF fd at
> > fd_array[256] (to check that 256 is ok). Or am I missing something?
> >
>
> That won't be enough, if I just pass insn->imm = id, insn->off = 257, it becomes
> first descriptor in kfunc_tab and kfunc_btf_tab. The total limit is 256, and
> they are kept in sorted order by based on id and off for the first, off for the
> second. So 256 different offs are needed (imm may be same actually), so that
> both fill up.
Just to test the 256 limit? I don't think it's necessary.
afaik there is no test that exercises the 64 map limit.
next prev parent reply other threads:[~2021-09-22 18:24 UTC|newest]
Thread overview: 31+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-09-20 14:15 [PATCH bpf-next v4 00/11] Support kernel module function calls from eBPF Kumar Kartikeya Dwivedi
2021-09-20 14:15 ` [PATCH bpf-next v4 01/11] bpf: Introduce BPF support for kernel module function calls Kumar Kartikeya Dwivedi
2021-09-20 14:15 ` [PATCH bpf-next v4 02/11] bpf: Be conservative while processing invalid kfunc calls Kumar Kartikeya Dwivedi
2021-09-20 14:15 ` [PATCH bpf-next v4 03/11] bpf: btf: Introduce helpers for dynamic BTF set registration Kumar Kartikeya Dwivedi
2021-09-20 14:15 ` [PATCH bpf-next v4 04/11] tools: Allow specifying base BTF file in resolve_btfids Kumar Kartikeya Dwivedi
2021-09-20 14:15 ` [PATCH bpf-next v4 05/11] bpf: Enable TCP congestion control kfunc from modules Kumar Kartikeya Dwivedi
2021-09-21 22:18 ` Andrii Nakryiko
2021-09-21 22:23 ` Kumar Kartikeya Dwivedi
2021-09-21 23:02 ` Andrii Nakryiko
2021-09-20 14:15 ` [PATCH bpf-next v4 06/11] libbpf: Support kernel module function calls Kumar Kartikeya Dwivedi
2021-09-21 22:41 ` Andrii Nakryiko
2021-09-24 23:54 ` Kumar Kartikeya Dwivedi
2021-09-25 0:30 ` Andrii Nakryiko
2021-09-20 14:15 ` [PATCH bpf-next v4 07/11] libbpf: Resolve invalid weak kfunc calls with imm = 0, off = 0 Kumar Kartikeya Dwivedi
2021-09-21 22:47 ` Andrii Nakryiko
2021-09-20 14:15 ` [PATCH bpf-next v4 08/11] libbpf: Update gen_loader to emit BTF_KIND_FUNC relocations Kumar Kartikeya Dwivedi
2021-09-21 0:57 ` Alexei Starovoitov
2021-09-21 4:50 ` Kumar Kartikeya Dwivedi
2021-09-21 19:04 ` Alexei Starovoitov
2021-09-21 22:25 ` Kumar Kartikeya Dwivedi
2021-09-20 14:15 ` [PATCH bpf-next v4 09/11] tools: bpftool: Add separate fd_array map support for light skeleton Kumar Kartikeya Dwivedi
2021-09-20 14:15 ` [PATCH bpf-next v4 10/11] libbpf: Fix skel_internal.h to set errno on loader retval < 0 Kumar Kartikeya Dwivedi
2021-09-20 14:15 ` [PATCH bpf-next v4 11/11] bpf: selftests: Add selftests for module kfunc support Kumar Kartikeya Dwivedi
2021-09-21 23:00 ` Andrii Nakryiko
2021-09-21 23:13 ` Kumar Kartikeya Dwivedi
2021-09-21 23:28 ` Kumar Kartikeya Dwivedi
2021-09-22 0:03 ` Andrii Nakryiko
2021-09-22 6:06 ` Kumar Kartikeya Dwivedi
2021-09-22 18:24 ` Alexei Starovoitov [this message]
2021-09-21 0:29 ` [PATCH bpf-next v4 00/11] Support kernel module function calls from eBPF Andrii Nakryiko
2021-09-21 4:55 ` Kumar Kartikeya Dwivedi
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='CAADnVQJb_mwxNRBdqaE_E=05V=YVHt5wrxSMigSYRMNvv4LWZg@mail.gmail.com' \
--to=alexei.starovoitov@gmail.com \
--cc=andrii.nakryiko@gmail.com \
--cc=andrii@kernel.org \
--cc=ast@kernel.org \
--cc=bpf@vger.kernel.org \
--cc=brouer@redhat.com \
--cc=daniel@iogearbox.net \
--cc=kafai@fb.com \
--cc=memxor@gmail.com \
--cc=netdev@vger.kernel.org \
--cc=songliubraving@fb.com \
--cc=toke@redhat.com \
--cc=yhs@fb.com \
/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
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
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).