Re: [PATCHv5 bpf-next 4/5] selftests: bpf: add test for sk_assign

From: Andrii Nakryiko <andrii.nakryiko@gmail.com>
To: Joe Stringer <joe@wand.net.nz>
Cc: bpf <bpf@vger.kernel.org>, Lorenz Bauer <lmb@cloudflare.com>,
	Networking <netdev@vger.kernel.org>,
	Daniel Borkmann <daniel@iogearbox.net>,
	Alexei Starovoitov <ast@kernel.org>,
	Eric Dumazet <eric.dumazet@gmail.com>, Martin Lau <kafai@fb.com>
Subject: Re: [PATCHv5 bpf-next 4/5] selftests: bpf: add test for sk_assign
Date: Fri, 3 Apr 2020 13:50:12 -0700	[thread overview]
Message-ID: <CAEf4BzaFbM+H1BRGeWTTTaBB_uwUxMadL-K7txFHJVWiGz34Tg@mail.gmail.com> (raw)
In-Reply-To: <CAOftzPj5aKspwmZ72t+ivjE72CUWObfgekpiQM+iCTya5hxgGw@mail.gmail.com>

On Thu, Apr 2, 2020 at 8:46 AM Joe Stringer <joe@wand.net.nz> wrote:
>
> I'll take a look. Should just be iproute2 package I believe.
>

For anyone following along. iproute2, which is now a dependency of
sk_assign selftest brings in a ton of dependencies, including systemd
itself. This, beyond causing linux image problems we haven't
investigated too deeply, also increases our image almost three-fold.
See [0] for github discussion on topic.

So for now I'm going to disable sk_assign selftest permanently in
libbpf tests. Ideally sk_assign can be written to not rely on iproute2
to set things up. But until then, it won't be exercised in libbpf's CI
tests, unfortunately.

  [0] https://github.com/libbpf/libbpf/pull/144#issuecomment-608170330

> On Wed, Apr 1, 2020, 16:20 Andrii Nakryiko <andrii.nakryiko@gmail.com> wrote:
>>
>> On Sun, Mar 29, 2020 at 3:58 PM Joe Stringer <joe@wand.net.nz> wrote:
>> >
>> > From: Lorenz Bauer <lmb@cloudflare.com>
>> >
>> > Attach a tc direct-action classifier to lo in a fresh network
>> > namespace, and rewrite all connection attempts to localhost:4321
>> > to localhost:1234 (for port tests) and connections to unreachable
>> > IPv4/IPv6 IPs to the local socket (for address tests). Includes
>> > implementations for both TCP and UDP.
>> >
>> > Keep in mind that both client to server and server to client traffic
>> > passes the classifier.
>> >
>> > Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
>> > Co-authored-by: Joe Stringer <joe@wand.net.nz>
>> > Signed-off-by: Joe Stringer <joe@wand.net.nz>
>> > Acked-by: Martin KaFai Lau <kafai@fb.com>
>> > ---
>> > v5: No change
>> > v4: Add acks
>> > v3: Add tests for UDP socket assign
>> >     Fix switching back to original netns after test
>> >     Avoid using signals to timeout connections
>> >     Refactor to iterate through test cases
>> > v2: Rebase onto test_progs infrastructure
>> > v1: Initial commit
>> > ---
>>
>> Hey Joe!
>>
>> When syncing libbpf to Github, this selftest is now failing with the
>> follow errors:
>>
>> tc: command line is not complete, try "help"
>> configure_stack:FAIL:46
>> configure_stack: Interrupted system call
>> #49 sk_assign:FAIL
>>
>> We are probably missing some packages or something like that. Could
>> you please help figuring out how we need to adjust libbpf Travis CI
>> environment to accomodate this? Thanks!
>> You can find one of the failed runs at [0]
>>
>>   [0] https://travis-ci.com/github/anakryiko/libbpf/jobs/311759005