From patchwork Thu Mar 18 19:40:35 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrii Nakryiko X-Patchwork-Id: 405317 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=-17.0 required=3.0 tests=BAYES_00, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT 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 C5F14C41518 for ; Thu, 18 Mar 2021 19:41:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A87AE64F1D for ; Thu, 18 Mar 2021 19:41:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233029AbhCRTl2 convert rfc822-to-8bit (ORCPT ); Thu, 18 Mar 2021 15:41:28 -0400 Received: from mx0b-00082601.pphosted.com ([67.231.153.30]:48674 "EHLO mx0a-00082601.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S232943AbhCRTlI (ORCPT ); Thu, 18 Mar 2021 15:41:08 -0400 Received: from pps.filterd (m0089730.ppops.net [127.0.0.1]) by m0089730.ppops.net (8.16.0.43/8.16.0.43) with SMTP id 12IJUZq5016647 for ; Thu, 18 Mar 2021 12:41:07 -0700 Received: from maileast.thefacebook.com ([163.114.130.16]) by m0089730.ppops.net with ESMTP id 37bs1h6ce8-2 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Thu, 18 Mar 2021 12:41:07 -0700 Received: from intmgw006.03.ash8.facebook.com (2620:10d:c0a8:1b::d) by mail.thefacebook.com (2620:10d:c0a8:83::6) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2176.2; Thu, 18 Mar 2021 12:41:06 -0700 Received: by devbig012.ftw2.facebook.com (Postfix, from userid 137359) id 00C9C2ED2588; Thu, 18 Mar 2021 12:41:05 -0700 (PDT) From: Andrii Nakryiko To: , , , CC: , Subject: [PATCH v4 bpf-next 11/12] selftests/bpf: pass all BPF .o's through BPF static linker Date: Thu, 18 Mar 2021 12:40:35 -0700 Message-ID: <20210318194036.3521577-12-andrii@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210318194036.3521577-1-andrii@kernel.org> References: <20210318194036.3521577-1-andrii@kernel.org> MIME-Version: 1.0 X-FB-Internal: Safe X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.369, 18.0.761 definitions=2021-03-18_12:2021-03-17,2021-03-18 signatures=0 X-Proofpoint-Spam-Details: rule=fb_default_notspam policy=fb_default score=0 lowpriorityscore=0 mlxscore=0 mlxlogscore=999 bulkscore=0 priorityscore=1501 clxscore=1015 phishscore=0 impostorscore=0 adultscore=0 suspectscore=0 spamscore=0 malwarescore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2009150000 definitions=main-2103180139 X-FB-Internal: deliver Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Pass all individual BPF object files (generated from progs/*.c) through `bpftool gen object` command to validate that BPF static linker doesn't corrupt them. As an additional sanity checks, validate that passing resulting object files through linker again results in identical ELF files. Exact same ELF contents can be guaranteed only after two passes, as after the first pass ELF sections order changes, and thus .BTF.ext data sections order changes. That, in turn, means that strings are added into the final BTF string sections in different order, so .BTF strings data might not be exactly the same. But doing another round of linking afterwards should result in the identical ELF file, which is checked with additional `diff` command. Signed-off-by: Andrii Nakryiko --- tools/testing/selftests/bpf/Makefile | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile index dbca39f45382..3a7c02add70c 100644 --- a/tools/testing/selftests/bpf/Makefile +++ b/tools/testing/selftests/bpf/Makefile @@ -355,12 +355,13 @@ $(TRUNNER_BPF_OBJS): $(TRUNNER_OUTPUT)/%.o: \ $$(call $(TRUNNER_BPF_BUILD_RULE),$$<,$$@, \ $(TRUNNER_BPF_CFLAGS)) -$(TRUNNER_BPF_SKELS): $(TRUNNER_OUTPUT)/%.skel.h: \ - $(TRUNNER_OUTPUT)/%.o \ - $(BPFTOOL) \ - | $(TRUNNER_OUTPUT) +$(TRUNNER_BPF_SKELS): %.skel.h: %.o $(BPFTOOL) | $(TRUNNER_OUTPUT) $$(call msg,GEN-SKEL,$(TRUNNER_BINARY),$$@) - $(Q)$$(BPFTOOL) gen skeleton $$< > $$@ + $(Q)$$(BPFTOOL) gen object $$(<:.o=.linked.o) $$< + $(Q)$$(BPFTOOL) gen object $$(<:.o=.linked2.o) $$(<:.o=.linked.o) + $(Q)$$(BPFTOOL) gen object $$(<:.o=.linked3.o) $$(<:.o=.linked2.o) + $(Q)diff $$(<:.o=.linked2.o) $$(<:.o=.linked3.o) + $(Q)$$(BPFTOOL) gen skeleton $$(<:.o=.linked.o) name $$(notdir $$(<:.o=)) > $$@ endif # ensure we set up tests.h header generation rule just once