From patchwork Mon Nov 9 21:00:19 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrii Nakryiko X-Patchwork-Id: 11892483 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=-7.0 required=3.0 tests=BAYES_00,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=no 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 DFA8EC2D0A3 for ; Mon, 9 Nov 2020 21:02:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A0CD92074F for ; Mon, 9 Nov 2020 21:02:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725946AbgKIVCc convert rfc822-to-8bit (ORCPT ); Mon, 9 Nov 2020 16:02:32 -0500 Received: from mx0b-00082601.pphosted.com ([67.231.153.30]:36744 "EHLO mx0a-00082601.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727070AbgKIVCc (ORCPT ); Mon, 9 Nov 2020 16:02:32 -0500 Received: from pps.filterd (m0001303.ppops.net [127.0.0.1]) by m0001303.ppops.net (8.16.0.42/8.16.0.42) with SMTP id 0A9KlJZN015758 for ; Mon, 9 Nov 2020 13:02:31 -0800 Received: from mail.thefacebook.com ([163.114.132.120]) by m0001303.ppops.net with ESMTP id 34nr4psw09-3 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Mon, 09 Nov 2020 13:02:30 -0800 Received: from intmgw001.08.frc2.facebook.com (2620:10d:c085:108::8) by mail.thefacebook.com (2620:10d:c085:11d::4) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1979.3; Mon, 9 Nov 2020 13:02:28 -0800 Received: by devbig012.ftw2.facebook.com (Postfix, from userid 137359) id DB9BE2EC924B; Mon, 9 Nov 2020 13:00:25 -0800 (PST) From: Andrii Nakryiko To: , , , CC: , , , , Andrii Nakryiko , Arnaldo Carvalho de Melo , Greg Kroah-Hartman Subject: [PATCH v3 bpf-next 0/5] Integrate kernel module BTF support Date: Mon, 9 Nov 2020 13:00:19 -0800 Message-ID: <20201109210024.2024572-1-andrii@kernel.org> X-Mailer: git-send-email 2.24.1 X-FB-Internal: Safe X-Proofpoint-UnRewURL: 0 URL was un-rewritten MIME-Version: 1.0 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.312,18.0.737 definitions=2020-11-09_13:2020-11-05,2020-11-09 signatures=0 X-Proofpoint-Spam-Details: rule=fb_default_notspam policy=fb_default score=0 lowpriorityscore=0 malwarescore=0 mlxlogscore=999 spamscore=0 suspectscore=0 mlxscore=0 bulkscore=0 phishscore=0 clxscore=1015 impostorscore=0 adultscore=0 priorityscore=1501 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2009150000 definitions=main-2011090138 X-FB-Internal: deliver Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net This patch set adds BTF generation for kernel modules using a compact split BTF approach. Respective patches have all the details. Kernel module BTFs rely on pahole's split BTF support, which is added in [0] and will be available starting from v1.19. Support for it is detected automatically during kernel build time. This patch set implements in-kernel support for split BTF loading and validation. It also extends GET_OBJ_INFO API for BTFs to return BTF's module name and a flag whether BTF itself is in-kernel or user-provided. vmlinux BTF is also exposed to user-space through the same BTF object iteration APIs. Follow up patch set will utilize the fact that vmlinux and module BTFs now have associated ID to provide ability to attach BPF fentry/fexit/etc programs to functions defined in kernel modules. bpftool is also extended to show module/vmlinux BTF's name. [0] https://patchwork.kernel.org/project/netdevbpf/list/?series=378699&state=* v2->v3: - get rid of unnecessary gotos (Song); v2->v1: - drop WARNs, add fewer pr_warn()'s instead (Greg); - properly initialize sysfs binary attribute structure (Greg); - add __maybe_unused to any_section_objs, used conditionally by module BTF; rfc->v1: - CONFIG_DEBUG_INFO_BTF_MODULES is derived automatically (Alexei); - vmlinux BTF now has explicit "vmlinux" name (Alexei); - added sysfs ABI documentation for /sys/kernel/btf/ (Greg). Cc: Arnaldo Carvalho de Melo Cc: Greg Kroah-Hartman Andrii Nakryiko (5): bpf: add in-kernel split BTF support bpf: assign ID to vmlinux BTF and return extra info for BTF in GET_OBJ_INFO kbuild: build kernel module BTFs if BTF is enabled and pahole supports it bpf: load and verify kernel module BTFs tools/bpftool: add support for in-kernel and named BTF in `btf show` Documentation/ABI/testing/sysfs-kernel-btf | 8 + include/linux/bpf.h | 2 + include/linux/module.h | 4 + include/uapi/linux/bpf.h | 3 + kernel/bpf/btf.c | 402 ++++++++++++++++++--- kernel/bpf/sysfs_btf.c | 2 +- kernel/module.c | 32 ++ lib/Kconfig.debug | 9 + scripts/Makefile.modfinal | 20 +- tools/bpf/bpftool/btf.c | 28 +- tools/include/uapi/linux/bpf.h | 3 + 11 files changed, 456 insertions(+), 57 deletions(-)