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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham 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 C88BBC433E1 for ; Fri, 12 Jun 2020 22:34:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A36BD206D7 for ; Fri, 12 Jun 2020 22:34:45 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=fb.com header.i=@fb.com header.b="nAIMYR6Z" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726307AbgFLWep (ORCPT ); Fri, 12 Jun 2020 18:34:45 -0400 Received: from mx0a-00082601.pphosted.com ([67.231.145.42]:47214 "EHLO mx0a-00082601.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726302AbgFLWep (ORCPT ); Fri, 12 Jun 2020 18:34:45 -0400 Received: from pps.filterd (m0044010.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 05CM6MgC025615 for ; Fri, 12 Jun 2020 15:34:44 -0700 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fb.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding : content-type; s=facebook; bh=cNRfGcbMbBf94VQ5FUSapjaaDr7Mz+2SNVUjQz4+BWc=; b=nAIMYR6Zx6d+Td3Q4Po0oUY0ZTBc7FNs7KNk/+cNc3wdSOzI6o5blA2tnhKy1iQR3o7u ePxXByqElpmg0/3PWPc4N/hpSTriJoHfOYQzYrfpKTLdjD7SCF+j2CUAaKLWqrrnTAn6 WbK0Qi74zvCzSeM1K/ZV+xQ20t31X/qx2Fw= Received: from mail.thefacebook.com ([163.114.132.120]) by mx0a-00082601.pphosted.com with ESMTP id 31kqwwy6j5-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Fri, 12 Jun 2020 15:34:44 -0700 Received: from intmgw003.08.frc2.facebook.com (2620:10d:c085:108::8) by mail.thefacebook.com (2620:10d:c085:11d::5) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1979.3; Fri, 12 Jun 2020 15:34:41 -0700 Received: by devbig012.ftw2.facebook.com (Postfix, from userid 137359) id B9D912EC1D14; Fri, 12 Jun 2020 15:32:04 -0700 (PDT) Smtp-Origin-Hostprefix: devbig From: Andrii Nakryiko Smtp-Origin-Hostname: devbig012.ftw2.facebook.com To: , , , CC: , , Andrii Nakryiko , Hao Luo , Arnaldo Carvalho de Melo , Song Liu , Quentin Monnet Smtp-Origin-Cluster: ftw2c04 Subject: [RFC PATCH bpf-next 3/8] selftests/bpf: add __ksym extern selftest Date: Fri, 12 Jun 2020 15:31:45 -0700 Message-ID: <20200612223150.1177182-4-andriin@fb.com> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20200612223150.1177182-1-andriin@fb.com> References: <20200612223150.1177182-1-andriin@fb.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-FB-Internal: Safe Content-Type: text/plain X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.216,18.0.687 definitions=2020-06-12_17:2020-06-12,2020-06-12 signatures=0 X-Proofpoint-Spam-Details: rule=fb_default_notspam policy=fb_default score=0 lowpriorityscore=0 mlxscore=0 mlxlogscore=859 spamscore=0 priorityscore=1501 impostorscore=0 malwarescore=0 phishscore=0 suspectscore=8 cotscore=-2147483648 adultscore=0 bulkscore=0 clxscore=1015 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2004280000 definitions=main-2006120164 X-FB-Internal: deliver Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org Validate libbpf is able to handle weak and strong kernel symbol externs i= n BPF code correctly. Signed-off-by: Andrii Nakryiko --- .../testing/selftests/bpf/prog_tests/ksyms.c | 71 +++++++++++++++++++ .../testing/selftests/bpf/progs/test_ksyms.c | 32 +++++++++ 2 files changed, 103 insertions(+) create mode 100644 tools/testing/selftests/bpf/prog_tests/ksyms.c create mode 100644 tools/testing/selftests/bpf/progs/test_ksyms.c diff --git a/tools/testing/selftests/bpf/prog_tests/ksyms.c b/tools/testi= ng/selftests/bpf/prog_tests/ksyms.c new file mode 100644 index 000000000000..8f041c9059ed --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/ksyms.c @@ -0,0 +1,71 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2019 Facebook */ + +#include +#include "test_ksyms.skel.h" +#include + +static int duration; + +static __u64 kallsyms_find(const char *sym) +{ + char type, name[256]; + unsigned long addr, res =3D 0; + FILE *f; + + f =3D fopen("/proc/kallsyms", "r"); + if (CHECK(!f, "kallsyms_fopen", "failed to open: %d\n", errno)) + return 0; + + while (fscanf(f, "%lx %c %s%*[^\n]\n", &addr, &type, name) > 0) { + if (strcmp(name, sym) =3D=3D 0) { + res =3D addr; + goto out; + } + } + + CHECK(false, "not_found", "symbol %s not found\n", sym); +out: + fclose(f); + return res; +} + +void test_ksyms(void) +{ + __u64 link_fops_addr =3D kallsyms_find("bpf_link_fops"); + const char *btf_path =3D "/sys/kernel/btf/vmlinux"; + struct test_ksyms *skel; + struct test_ksyms__data *data; + struct stat st; + __u64 btf_size; + int err; + + if (CHECK(stat(btf_path, &st), "stat_btf", "err %d\n", errno)) + return; + btf_size =3D st.st_size; + + skel =3D test_ksyms__open_and_load(); + if (CHECK(!skel, "skel_open", "failed to open and load skeleton\n")) + return; + + err =3D test_ksyms__attach(skel); + if (CHECK(err, "skel_attach", "skeleton attach failed: %d\n", err)) + goto cleanup; + + /* trigger tracepoint */ + usleep(1); + + data =3D skel->data; + CHECK(data->out__bpf_link_fops !=3D link_fops_addr, "bpf_link_fops", + "got 0x%llx, exp 0x%llx\n", + data->out__bpf_link_fops, link_fops_addr); + CHECK(data->out__bpf_link_fops1 !=3D 0, "bpf_link_fops1", + "got %llu, exp %llu\n", data->out__bpf_link_fops1, (__u64)0); + CHECK(data->out__btf_size !=3D btf_size, "btf_size", + "got %llu, exp %llu\n", data->out__btf_size, btf_size); + CHECK(data->out__fixed_percpu_data !=3D 0, "fixed_percpu_data", + "got %llu, exp %llu\n", data->out__fixed_percpu_data, (__u64)0); + +cleanup: + test_ksyms__destroy(skel); +} diff --git a/tools/testing/selftests/bpf/progs/test_ksyms.c b/tools/testi= ng/selftests/bpf/progs/test_ksyms.c new file mode 100644 index 000000000000..598d6749b691 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_ksyms.c @@ -0,0 +1,32 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2019 Facebook */ + +#include +#include +#include + +__u64 out__bpf_link_fops =3D -1; +__u64 out__bpf_link_fops1 =3D -1; +__u64 out__btf_size =3D -1; +__u64 out__fixed_percpu_data =3D -1; + +extern const void bpf_link_fops __ksym; +/* non-existing symbol, weak, default to zero */ +extern const void bpf_link_fops1 __ksym __weak; +extern const void __start_BTF __ksym; +extern const void __stop_BTF __ksym; +/* fixed_percpu_data is always at zero offset */ +extern const void fixed_percpu_data __ksym; + +SEC("raw_tp/sys_enter") +int handler(const void *ctx) +{ + out__bpf_link_fops =3D (__u64)&bpf_link_fops; + out__bpf_link_fops1 =3D (__u64)&bpf_link_fops1; + out__btf_size =3D (__u64)(&__stop_BTF - &__start_BTF); + out__fixed_percpu_data =3D (__u64)&fixed_percpu_data; + + return 0; +} + +char _license[] SEC("license") =3D "GPL"; --=20 2.24.1