From patchwork Wed Aug 2 07:39:06 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alan Maguire X-Patchwork-Id: 13337775 X-Patchwork-Delegate: bpf@iogearbox.net Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3ED6C1859 for ; Wed, 2 Aug 2023 07:40:01 +0000 (UTC) Received: from mx0a-00069f02.pphosted.com (mx0a-00069f02.pphosted.com [205.220.165.32]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2AF754682 for ; Wed, 2 Aug 2023 00:39:39 -0700 (PDT) Received: from pps.filterd (m0333521.ppops.net [127.0.0.1]) by mx0b-00069f02.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 371KxjfD026106; Wed, 2 Aug 2023 07:39:12 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=from : to : cc : subject : date : message-id : mime-version : content-transfer-encoding; s=corp-2023-03-30; bh=J8Ao0y3j5TNBhCEP/tdsSpJi1XQycCUVNr+X7nMR31E=; b=Cbv3f3GuLdJHdTBYa1h2EJHGmzNfU196hP8B08EvTDvmsy0oQgfLFmIsMrcKFLCiubYM Hmcz6+uCNeNp1NhKF7tVL22UmJnNxycP1e2+qY9F7f3zJmjAd/iZfU6r4m/SYhCzW9WH LgwLxt+J9nNxHZN1Q3fVOhEVyU7FCgqsuXJ4hkSv9whdkDMGjZKOxYI/tUhQaP4jmmJ0 FHvoYTmgYfDO9gCqzoRzP16wzCeV7uEDoOgMiRW8coVGUH17hrpGClPVl037jEEPH6oK xECpf5WiJwvrvy3N02uu2TD7wUazuhSVAwKxGp+AqmvZQUQKUOQO254d+acGnxpX9i7d pw== Received: from iadpaimrmta01.imrmtpd1.prodappiadaev1.oraclevcn.com (iadpaimrmta01.appoci.oracle.com [130.35.100.223]) by mx0b-00069f02.pphosted.com (PPS) with ESMTPS id 3s4spc6nkv-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 02 Aug 2023 07:39:12 +0000 Received: from pps.filterd (iadpaimrmta01.imrmtpd1.prodappiadaev1.oraclevcn.com [127.0.0.1]) by iadpaimrmta01.imrmtpd1.prodappiadaev1.oraclevcn.com (8.17.1.19/8.17.1.19) with ESMTP id 3726vnQf000737; Wed, 2 Aug 2023 07:39:11 GMT Received: from pps.reinject (localhost [127.0.0.1]) by iadpaimrmta01.imrmtpd1.prodappiadaev1.oraclevcn.com (PPS) with ESMTPS id 3s4s7dkbd9-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 02 Aug 2023 07:39:11 +0000 Received: from iadpaimrmta01.imrmtpd1.prodappiadaev1.oraclevcn.com (iadpaimrmta01.imrmtpd1.prodappiadaev1.oraclevcn.com [127.0.0.1]) by pps.reinject (8.17.1.5/8.17.1.5) with ESMTP id 3727dAeM015242; Wed, 2 Aug 2023 07:39:10 GMT Received: from bpf.uk.oracle.com (dhcp-10-175-173-85.vpn.oracle.com [10.175.173.85]) by iadpaimrmta01.imrmtpd1.prodappiadaev1.oraclevcn.com (PPS) with ESMTP id 3s4s7dkbah-1; Wed, 02 Aug 2023 07:39:10 +0000 From: Alan Maguire To: yhs@fb.com, ast@kernel.org, andrii@kernel.org Cc: martin.lau@linux.dev, song@kernel.org, john.fastabend@gmail.com, kpsingh@kernel.org, sdf@google.com, haoluo@google.com, jolsa@kernel.org, mykolal@fb.com, bpf@vger.kernel.org, Alan Maguire , Colm Harrington Subject: [PATCH v2 bpf] selftests/bpf: fix static assert compilation issue for test_cls_*.c Date: Wed, 2 Aug 2023 08:39:06 +0100 Message-Id: <20230802073906.3197480-1-alan.maguire@oracle.com> X-Mailer: git-send-email 2.39.3 Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.254,Aquarius:18.0.957,Hydra:6.0.591,FMLib:17.11.176.26 definitions=2023-08-02_03,2023-08-01_01,2023-05-22_02 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 phishscore=0 bulkscore=0 suspectscore=0 adultscore=0 mlxlogscore=999 spamscore=0 malwarescore=0 mlxscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2306200000 definitions=main-2308020067 X-Proofpoint-ORIG-GUID: yBIofNBFqYShNSKu0-0MMBEBdjheNCwL X-Proofpoint-GUID: yBIofNBFqYShNSKu0-0MMBEBdjheNCwL X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF, RCVD_IN_DNSWL_BLOCKED,RCVD_IN_MSPIKE_H5,RCVD_IN_MSPIKE_WL, SPF_HELO_NONE,SPF_NONE,T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net X-Patchwork-Delegate: bpf@iogearbox.net commit bdeeed3498c7 ("libbpf: fix offsetof() and container_of() to work with CO-RE") ...was backported to stable trees such as 5.15. The problem is that with older LLVM/clang (14/15) - which is often used for older kernels - we see compilation failures in BPF selftests now: In file included from progs/test_cls_redirect_subprogs.c:2: progs/test_cls_redirect.c:90:2: error: static assertion expression is not an integral constant expression sizeof(flow_ports_t) != ^~~~~~~~~~~~~~~~~~~~~~~ progs/test_cls_redirect.c:91:3: note: cast that performs the conversions of a reinterpret_cast is not allowed in a constant expression offsetofend(struct bpf_sock_tuple, ipv4.dport) - ^ progs/test_cls_redirect.c:32:3: note: expanded from macro 'offsetofend' (offsetof(TYPE, MEMBER) + sizeof((((TYPE *)0)->MEMBER))) ^ tools/testing/selftests/bpf/tools/include/bpf/bpf_helpers.h:86:33: note: expanded from macro 'offsetof' ^ In file included from progs/test_cls_redirect_subprogs.c:2: progs/test_cls_redirect.c:95:2: error: static assertion expression is not an integral constant expression sizeof(flow_ports_t) != ^~~~~~~~~~~~~~~~~~~~~~~ progs/test_cls_redirect.c:96:3: note: cast that performs the conversions of a reinterpret_cast is not allowed in a constant expression offsetofend(struct bpf_sock_tuple, ipv6.dport) - ^ progs/test_cls_redirect.c:32:3: note: expanded from macro 'offsetofend' (offsetof(TYPE, MEMBER) + sizeof((((TYPE *)0)->MEMBER))) ^ tools/testing/selftests/bpf/tools/include/bpf/bpf_helpers.h:86:33: note: expanded from macro 'offsetof' ^ 2 errors generated. make: *** [Makefile:594: tools/testing/selftests/bpf/test_cls_redirect_subprogs.bpf.o] Error 1 The problem is the new offsetof() does not play nice with static asserts. Given that the context is a static assert (and CO-RE relocation is not needed at compile time), offsetof() usage can be replaced by restoring the original offsetof() definition as __builtin_offsetof(). Fixes: bdeeed3498c7 ("libbpf: fix offsetof() and container_of() to work with CO-RE") Reported-by: Colm Harrington Signed-off-by: Alan Maguire Tested-by: Yipeng Zou Acked-by: Yonghong Song --- Changes since v1: - simplified to restore offsetof() definition in test_cls_redirect.h, and added explanatory comment (Yonghong) --- tools/testing/selftests/bpf/progs/test_cls_redirect.h | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/tools/testing/selftests/bpf/progs/test_cls_redirect.h b/tools/testing/selftests/bpf/progs/test_cls_redirect.h index 76eab0aacba0..233b089d1fba 100644 --- a/tools/testing/selftests/bpf/progs/test_cls_redirect.h +++ b/tools/testing/selftests/bpf/progs/test_cls_redirect.h @@ -12,6 +12,15 @@ #include #include +/* offsetof() is used in static asserts, and the libbpf-redefined CO-RE + * friendly version breaks compilation for older clang versions <= 15 + * when invoked in a static assert. Restore original here. + */ +#ifdef offsetof +#undef offsetof +#define offsetof(type, member) __builtin_offsetof(type, member) +#endif + struct gre_base_hdr { uint16_t flags; uint16_t protocol;