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=-11.5 required=3.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED,DKIM_INVALID,DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,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 712FFC433E1 for ; Wed, 19 Aug 2020 22:40:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 47234206B5 for ; Wed, 19 Aug 2020 22:40:40 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=google.com header.i=@google.com header.b="WC45bL65" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727846AbgHSWkh (ORCPT ); Wed, 19 Aug 2020 18:40:37 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41858 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726466AbgHSWkf (ORCPT ); Wed, 19 Aug 2020 18:40:35 -0400 Received: from mail-qt1-x849.google.com (mail-qt1-x849.google.com [IPv6:2607:f8b0:4864:20::849]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DFB19C061383 for ; Wed, 19 Aug 2020 15:40:34 -0700 (PDT) Received: by mail-qt1-x849.google.com with SMTP id s29so139089qtc.12 for ; Wed, 19 Aug 2020 15:40:34 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=sender:date:message-id:mime-version:subject:from:to:cc; bh=EvVX+342SXuaBchy3/trMWGY/3AxdBYSkIWLg0jDdX0=; b=WC45bL657ajNciULhddNw2JgJ3L33JA7MxGDn+WyCv9HIfw/NxIXHtYJgr5s/NQ+Au GQ1KnB/WhKjdtqvnAl+B6R9wOUaRCRhVl1RHzge9cE3ZT/WHNrcuhe1r6pY7ssjl640n oxMKCcMjdCzO1jSde2y84+mogDdCbH+boQ3kaD0nUm+lHMC4aar+44tEwgmFGnx693Nb ICm6Amk423FRPU9gp28mVjfus4Z6p0jXbuCrv1kRmSE40AzDs70Kxz736HfHvezfbH48 1JXBKXM2g/UV/HI8d2ml9An0tBUUZlxGSZxpA/dsSqWtd8Ayn8oyjUdJIFPaybef7IS7 FP1g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:message-id:mime-version:subject:from :to:cc; bh=EvVX+342SXuaBchy3/trMWGY/3AxdBYSkIWLg0jDdX0=; b=lV7Pjt4cygagR1xXLvmTfo2Mais/Z5u1Sl1mQHYX11xnFzK1WeeCJ5MU0z5ws+sUl1 NN82G20UGpEijAleOkkjiohztrxAzPawz/0HL2fi/OnGsEmZXk9nbCl3aB2NQ9NSeR42 iNRdNeyTOIXzWcOdtrkiopfWjc7WglbOGxmsn1m/elbhnz1G2c0GmwFQOmEYW4Bb/tZ2 WvPTkX0Q8MXSpAlRwBtr+RMNEbxDTYD9JDqWGQeum4SfWvaa7CpLYXZx1MN7Lo9fWtIt Vb9Pg2l16L/+QmnVXRUn6KpvTphxrLOYJWFh3vj8gv39r/BhNIgs5KljG6WCmiSUcrOo AU6Q== X-Gm-Message-State: AOAM533a2VSqtjOEHdXAnZFQLEMEz6dVZmcmjLXvvOU/MHYUEpeg5oud kwWYPfnES2pmnRTX+/a7BEW4Eq27TvY= X-Google-Smtp-Source: ABdhPJxXcTQc4F9HjvdGQaSU0zuQOKiQ7mlX9TYnvGKi6DOmfJ4Myqy4u5T27jdfalORwFRyTn4kdYrF4no= X-Received: from haoluo.svl.corp.google.com ([2620:15c:2cd:202:f693:9fff:fef4:e444]) (user=haoluo job=sendgmr) by 2002:a0c:c248:: with SMTP id w8mr450623qvh.157.1597876834030; Wed, 19 Aug 2020 15:40:34 -0700 (PDT) Date: Wed, 19 Aug 2020 15:40:22 -0700 Message-Id: <20200819224030.1615203-1-haoluo@google.com> Mime-Version: 1.0 X-Mailer: git-send-email 2.28.0.220.ged08abb693-goog Subject: [PATCH bpf-next v1 0/8] bpf: BTF support for ksyms From: Hao Luo To: netdev@vger.kernel.org, bpf@vger.kernel.org, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org Cc: Shuah Khan , Alexei Starovoitov , Andrii Nakryiko , Daniel Borkmann , Martin KaFai Lau , Song Liu , Yonghong Song , John Fastabend , KP Singh , Quentin Monnet , Hao Luo , Steven Rostedt , Ingo Molnar , Andrey Ignatov , Jakub Sitnicki Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This patch series extends the previously added __ksym externs with btf support. Right now the __ksym externs are treated as pure 64-bit scalar value. Libbpf replaces ld_imm64 insn of __ksym by its kernel address at load time. This patch series extend those externs with their btf info. Note that btf support for __ksym must come with the kernel btf that has VARs encoded to work properly. The corresponding chagnes in pahole is available at [1]. The first 5 patches in this series add support for general kernel global variables, which includes verifier checking (01/08), libbpf type checking (03/08) and btf_id resolving (04/08). The last 3 patches extends that capability further by introducing a helper bpf_per_cpu_ptr(), which allows accessing kernel percpu vars correctly (06/08). The tests of this feature were performed against the extended pahole. For kernel btf that does not have VARs encoded, the selftests will be skipped. [1] https://git.kernel.org/pub/scm/devel/pahole/pahole.git/commit/?id=f3d9054ba8ff1df0fc44e507e3a01c0964cabd42 rfc -> v1: - Encode VAR's btf_id for PSEUDO_BTF_ID. - More checks in verifier. Checking the btf_id passed as PSEUDO_BTF_ID is valid VAR, its name and type. - Checks in libbpf on type compatibility of ksyms. - Add bpf_per_cpu_ptr() to access kernel percpu vars. Introduced new ARG and RET types for this helper. Hao Luo (8): bpf: Introduce pseudo_btf_id bpf: Propagate BPF_PSEUDO_BTF_ID to uapi headers in /tools bpf: Introduce help function to validate ksym's type. bpf/libbpf: BTF support for typed ksyms bpf/selftests: ksyms_btf to test typed ksyms bpf: Introduce bpf_per_cpu_ptr() bpf: Propagate bpf_per_cpu_ptr() to /tools bpf/selftests: Test for bpf_per_cpu_ptr() include/linux/bpf.h | 3 + include/linux/btf.h | 26 +++ include/uapi/linux/bpf.h | 52 +++++- kernel/bpf/btf.c | 25 --- kernel/bpf/verifier.c | 128 ++++++++++++- kernel/trace/bpf_trace.c | 18 ++ tools/include/uapi/linux/bpf.h | 53 +++++- tools/lib/bpf/btf.c | 171 ++++++++++++++++++ tools/lib/bpf/btf.h | 2 + tools/lib/bpf/libbpf.c | 130 +++++++++++-- .../selftests/bpf/prog_tests/ksyms_btf.c | 81 +++++++++ .../selftests/bpf/progs/test_ksyms_btf.c | 36 ++++ 12 files changed, 665 insertions(+), 60 deletions(-) create mode 100644 tools/testing/selftests/bpf/prog_tests/ksyms_btf.c create mode 100644 tools/testing/selftests/bpf/progs/test_ksyms_btf.c -- 2.28.0.220.ged08abb693-goog