From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A410EC433B4 for ; Thu, 8 Apr 2021 11:59:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7063E61158 for ; Thu, 8 Apr 2021 11:59:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231240AbhDHL7v (ORCPT ); Thu, 8 Apr 2021 07:59:51 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:38130 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231194AbhDHL7u (ORCPT ); Thu, 8 Apr 2021 07:59:50 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1617883179; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=qijMefmIa45ZdhR9YEweDU07OhF4NJOr6eTWwpRgQ2g=; b=AEyc4wfG5+rCsMhRLXnuEK5QggFC5RkNf8TXKZXJwwBxKvFYG4JsJEghIN3arnV2NN2gfu oKpKc3z0E0t1TwU8m2jUxOeIMN17UI9EqgNtRK/yq4mbzIkmR+HVTYHfwgPHNA+ngERfHl tmM1ObcTgVMT2f66KmazmIcTVEvheks= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-351-mH7BT3bLOV2DNUAMcevOqw-1; Thu, 08 Apr 2021 07:59:35 -0400 X-MC-Unique: mH7BT3bLOV2DNUAMcevOqw-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 1DECA107ACC7; Thu, 8 Apr 2021 11:59:32 +0000 (UTC) Received: from krava (unknown [10.40.195.201]) by smtp.corp.redhat.com (Postfix) with SMTP id 3EC4D5D71D; Thu, 8 Apr 2021 11:59:25 +0000 (UTC) Date: Thu, 8 Apr 2021 13:59:25 +0200 From: Jiri Olsa To: Andrii Nakryiko Cc: Jiri Olsa , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Networking , bpf , Martin KaFai Lau , Song Liu , Yonghong Song , John Fastabend , KP Singh , Toke =?iso-8859-1?Q?H=F8iland-J=F8rgensen?= Subject: Re: [PATCHv2 bpf-next 5/5] selftests/bpf: Test that module can't be unloaded with attached trampoline Message-ID: References: <20210406212913.970917-1-jolsa@kernel.org> <20210406212913.970917-6-jolsa@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Wed, Apr 07, 2021 at 04:04:48PM -0700, Andrii Nakryiko wrote: > On Wed, Apr 7, 2021 at 4:22 AM Jiri Olsa wrote: > > > > Adding test to verify that once we attach module's trampoline, > > the module can't be unloaded. > > > > Signed-off-by: Jiri Olsa > > --- > > To be fair, to test that you are actually testing what you think you > are testing, you'd have to prove that you *can* detach when no program > is attached to bpf_testmod ;) You'd also need kern_sync_rcu() to wait > for all the async clean up to complete inside the kernel. But that > doesn't interact with other tests well, so I think it's fine. well without the kernel change the module gets unloaded and the test below fails.. we could add module unload test, but as you described it could probably interfere with other tests > > grumpily due to CHECK() usage (please do consider updating to ASSERT): ok, will check thanks, jirka > > Acked-by: Andrii Nakryiko > > > .../selftests/bpf/prog_tests/module_attach.c | 23 +++++++++++++++++++ > > 1 file changed, 23 insertions(+) > > > > diff --git a/tools/testing/selftests/bpf/prog_tests/module_attach.c b/tools/testing/selftests/bpf/prog_tests/module_attach.c > > index 5bc53d53d86e..d180b8c28287 100644 > > --- a/tools/testing/selftests/bpf/prog_tests/module_attach.c > > +++ b/tools/testing/selftests/bpf/prog_tests/module_attach.c > > @@ -45,12 +45,18 @@ static int trigger_module_test_write(int write_sz) > > return 0; > > } > > > > +static int delete_module(const char *name, int flags) > > +{ > > + return syscall(__NR_delete_module, name, flags); > > +} > > + > > void test_module_attach(void) > > { > > const int READ_SZ = 456; > > const int WRITE_SZ = 457; > > struct test_module_attach* skel; > > struct test_module_attach__bss *bss; > > + struct bpf_link *link; > > int err; > > > > skel = test_module_attach__open(); > > @@ -84,6 +90,23 @@ void test_module_attach(void) > > ASSERT_EQ(bss->fexit_ret, -EIO, "fexit_tet"); > > ASSERT_EQ(bss->fmod_ret_read_sz, READ_SZ, "fmod_ret"); > > > > + test_module_attach__detach(skel); > > + > > + /* attach fentry/fexit and make sure it get's module reference */ > > + link = bpf_program__attach(skel->progs.handle_fentry); > > + if (CHECK(IS_ERR(link), "attach_fentry", "err: %ld\n", PTR_ERR(link))) > > + goto cleanup; > > + > > + ASSERT_ERR(delete_module("bpf_testmod", 0), "delete_module"); > > + bpf_link__destroy(link); > > + > > + link = bpf_program__attach(skel->progs.handle_fexit); > > + if (CHECK(IS_ERR(link), "attach_fexit", "err: %ld\n", PTR_ERR(link))) > > + goto cleanup; > > + > > + ASSERT_ERR(delete_module("bpf_testmod", 0), "delete_module"); > > + bpf_link__destroy(link); > > + > > cleanup: > > test_module_attach__destroy(skel); > > } > > -- > > 2.30.2 > > >