From patchwork Fri Dec 11 01:59:46 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrii Nakryiko X-Patchwork-Id: 342636 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 EDFBAC0018C for ; Fri, 11 Dec 2020 02:01:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CBDA323EB0 for ; Fri, 11 Dec 2020 02:01:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389728AbgLKCBQ convert rfc822-to-8bit (ORCPT ); Thu, 10 Dec 2020 21:01:16 -0500 Received: from mx0b-00082601.pphosted.com ([67.231.153.30]:56576 "EHLO mx0b-00082601.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2395027AbgLKCAk (ORCPT ); Thu, 10 Dec 2020 21:00:40 -0500 Received: from pps.filterd (m0109332.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.16.0.43/8.16.0.43) with SMTP id 0BB1oAkM000677 for ; Thu, 10 Dec 2020 17:59:59 -0800 Received: from maileast.thefacebook.com ([163.114.130.16]) by mx0a-00082601.pphosted.com with ESMTP id 35b68sgwbe-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Thu, 10 Dec 2020 17:59:59 -0800 Received: from intmgw004.03.ash8.facebook.com (2620:10d:c0a8:1b::d) by mail.thefacebook.com (2620:10d:c0a8:82::f) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1979.3; Thu, 10 Dec 2020 17:59:52 -0800 Received: by devbig012.ftw2.facebook.com (Postfix, from userid 137359) id 7C7132ECB180; Thu, 10 Dec 2020 17:59:48 -0800 (PST) From: Andrii Nakryiko To: , , , CC: , , Alexei Starovoitov Subject: [PATCH bpf-next] selftests/bpf: fix bpf_testmod.ko recompilation logic Date: Thu, 10 Dec 2020 17:59:46 -0800 Message-ID: <20201211015946.4062098-1-andrii@kernel.org> X-Mailer: git-send-email 2.24.1 MIME-Version: 1.0 X-FB-Internal: Safe X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.343, 18.0.737 definitions=2020-12-10_11:2020-12-09,2020-12-10 signatures=0 X-Proofpoint-Spam-Details: rule=fb_default_notspam policy=fb_default score=0 priorityscore=1501 bulkscore=0 mlxlogscore=999 malwarescore=0 adultscore=0 spamscore=0 phishscore=0 lowpriorityscore=0 mlxscore=0 clxscore=1015 impostorscore=0 suspectscore=9 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2009150000 definitions=main-2012110010 X-FB-Internal: deliver Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org bpf_testmod.ko build rule declared dependency on VMLINUX_BTF, but the variable itself was initialized after the rule was declared, which often caused bpf_testmod.ko to not be re-compiled. Fix by moving VMLINUX_BTF determination sooner. Also enforce bpf_testmod.ko recompilation when we detect that vmlinux image changed by removing bpf_testmod/bpf_testmod.ko. This is necessary to generate correct module's split BTF. Without it, Kbuild's module build logic might determine that nothing changed on the kernel side and thus bpf_testmod.ko shouldn't be rebuilt, so won't re-generate module BTF, which often leads to module's BTF with wrong string offsets against vmlinux BTF. Removing .ko file forces Kbuild to re-build the module. Reported-by: Alexei Starovoitov Fixes: 9f7fa225894c ("selftests/bpf: Add bpf_testmod kernel module for testing") Signed-off-by: Andrii Nakryiko --- tools/testing/selftests/bpf/Makefile | 15 ++++++++------- 1 file changed, 8 insertions(+), 7 deletions(-) diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile index 50b3495d7ddf..8b515a17f44b 100644 --- a/tools/testing/selftests/bpf/Makefile +++ b/tools/testing/selftests/bpf/Makefile @@ -116,6 +116,13 @@ INCLUDE_DIR := $(SCRATCH_DIR)/include BPFOBJ := $(BUILD_DIR)/libbpf/libbpf.a RESOLVE_BTFIDS := $(BUILD_DIR)/resolve_btfids/resolve_btfids +VMLINUX_BTF_PATHS ?= $(if $(O),$(O)/vmlinux) \ + $(if $(KBUILD_OUTPUT),$(KBUILD_OUTPUT)/vmlinux) \ + ../../../../vmlinux \ + /sys/kernel/btf/vmlinux \ + /boot/vmlinux-$(shell uname -r) +VMLINUX_BTF ?= $(abspath $(firstword $(wildcard $(VMLINUX_BTF_PATHS)))) + # Define simple and short `make test_progs`, `make test_sysctl`, etc targets # to build individual tests. # NOTE: Semicolon at the end is critical to override lib.mk's default static @@ -140,6 +147,7 @@ $(OUTPUT)/urandom_read: urandom_read.c $(OUTPUT)/bpf_testmod.ko: $(VMLINUX_BTF) $(wildcard bpf_testmod/Makefile bpf_testmod/*.[ch]) $(call msg,MOD,,$@) + $(Q)$(RM) bpf_testmod/bpf_testmod.ko # force re-compilation $(Q)$(MAKE) $(submake_extras) -C bpf_testmod $(Q)cp bpf_testmod/bpf_testmod.ko $@ @@ -147,13 +155,6 @@ $(OUTPUT)/test_stub.o: test_stub.c $(BPFOBJ) $(call msg,CC,,$@) $(Q)$(CC) -c $(CFLAGS) -o $@ $< -VMLINUX_BTF_PATHS ?= $(if $(O),$(O)/vmlinux) \ - $(if $(KBUILD_OUTPUT),$(KBUILD_OUTPUT)/vmlinux) \ - ../../../../vmlinux \ - /sys/kernel/btf/vmlinux \ - /boot/vmlinux-$(shell uname -r) -VMLINUX_BTF ?= $(abspath $(firstword $(wildcard $(VMLINUX_BTF_PATHS)))) - DEFAULT_BPFTOOL := $(SCRATCH_DIR)/sbin/bpftool $(OUTPUT)/runqslower: $(BPFOBJ) | $(DEFAULT_BPFTOOL)