From patchwork Wed Jul 1 06:45:23 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrii Nakryiko X-Patchwork-Id: 1320271 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Original-To: incoming-bpf@patchwork.ozlabs.org Delivered-To: patchwork-incoming-bpf@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=bpf-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=reject dis=none) header.from=fb.com Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=fb.com header.i=@fb.com header.a=rsa-sha256 header.s=facebook header.b=JF6ayrA9; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 49xWvS2SNzz9s1x for ; Wed, 1 Jul 2020 16:45:40 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727970AbgGAGpi (ORCPT ); Wed, 1 Jul 2020 02:45:38 -0400 Received: from mx0a-00082601.pphosted.com ([67.231.145.42]:54778 "EHLO mx0a-00082601.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727968AbgGAGpi (ORCPT ); Wed, 1 Jul 2020 02:45:38 -0400 Received: from pps.filterd (m0044012.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 0616fAYl008221 for ; Tue, 30 Jun 2020 23:45:37 -0700 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fb.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding : content-type; s=facebook; bh=jqUwwYpFA1EqVwoHCCH4zCzzCGaoLEOB4aLchWeaIEY=; b=JF6ayrA9dM8n9z0IJdbWUqE2INztKhQPTWn0OzyLHCv29zKyzO3BwG5LD0PSujpsK02E T5ybzBRfbQpnL2RsypR3gmbnVyIFXF6+AaKON7F17SaJDjq/HcKfbo5VA64sOo4/tT7A q2B0J3Z4sGwD2JWjCtTz65IO0Oo4HAY0WQ0= Received: from maileast.thefacebook.com ([163.114.130.16]) by mx0a-00082601.pphosted.com with ESMTP id 320bcdta11-2 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Tue, 30 Jun 2020 23:45:37 -0700 Received: from intmgw002.03.ash8.facebook.com (2620:10d:c0a8:1b::d) by mail.thefacebook.com (2620:10d:c0a8:82::d) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1979.3; Tue, 30 Jun 2020 23:45:35 -0700 Received: by devbig012.ftw2.facebook.com (Postfix, from userid 137359) id 3ADA72EC3A2B; Tue, 30 Jun 2020 23:45:31 -0700 (PDT) Smtp-Origin-Hostprefix: devbig From: Andrii Nakryiko Smtp-Origin-Hostname: devbig012.ftw2.facebook.com To: , , , CC: , , Andrii Nakryiko , Anton Protopopov , Daniel Xu Smtp-Origin-Cluster: ftw2c04 Subject: [PATCH bpf-next 1/3] libbpf: support stripping modifiers for btf_dump Date: Tue, 30 Jun 2020 23:45:23 -0700 Message-ID: <20200701064527.3158178-2-andriin@fb.com> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20200701064527.3158178-1-andriin@fb.com> References: <20200701064527.3158178-1-andriin@fb.com> MIME-Version: 1.0 X-FB-Internal: Safe X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.235, 18.0.687 definitions=2020-07-01_03:2020-07-01,2020-07-01 signatures=0 X-Proofpoint-Spam-Details: rule=fb_default_notspam policy=fb_default score=0 mlxscore=0 lowpriorityscore=0 malwarescore=0 bulkscore=0 mlxlogscore=999 impostorscore=0 adultscore=0 cotscore=-2147483648 spamscore=0 suspectscore=0 phishscore=0 clxscore=1015 priorityscore=1501 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2004280000 definitions=main-2007010047 X-FB-Internal: deliver Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org One important use case when emitting const/volatile/restrict is undesirable is BPF skeleton generation of DATASEC layout. These are further memory-mapped and can be written/read from user-space directly. For important case of .rodata variables, bpftool strips away first-level modifiers, to make their use on user-space side simple and not requiring extra type casts to override compiler complaining about writing to const variables. This logic works mostly fine, but breaks in some more complicated cases. E.g.: const volatile int params[10]; Because in BTF it's a chain of ARRAY -> CONST -> VOLATILE -> INT, bpftool stops at ARRAY and doesn't strip CONST and VOLATILE. In skeleton this variable will be emitted as is. So when used from user-space, compiler will complain about writing to const array. This is problematic, as also mentioned in [0]. To solve this for arrays and other non-trivial cases (e.g., inner const/volatile fields inside the struct), teach btf_dump to strip away any modifier, when requested. This patch converts existing struct btf_dump_opts to modern opts "framework" with size field and easily extensible in the future with backwards/forward compatibility. While this is a breaking change, there are only two known clients of this API: bpftool and bpftrace. bpftool hasn't used opts and just passed NULL, so is not affected and subsequent patch makes it use using DECLARE_LIBBPF_OPTS() macro. bpftrace does use opts and I'll work with bpftrace maintainers to adopt to a new opts style. While a bit painful, it seems like a better strategy long-term, instead of maintaining two sets of btf_dump opts and constructors. [0] https://github.com/iovisor/bcc/pull/2994#issuecomment-650588533 Cc: Daniel Xu Reported-by: Anton Protopopov Signed-off-by: Andrii Nakryiko --- tools/lib/bpf/btf.h | 6 ++++++ tools/lib/bpf/btf_dump.c | 18 +++++++++++++----- 2 files changed, 19 insertions(+), 5 deletions(-) diff --git a/tools/lib/bpf/btf.h b/tools/lib/bpf/btf.h index 06cd1731c154..5c2acca8d7f4 100644 --- a/tools/lib/bpf/btf.h +++ b/tools/lib/bpf/btf.h @@ -115,8 +115,14 @@ LIBBPF_API int btf__dedup(struct btf *btf, struct btf_ext *btf_ext, struct btf_dump; struct btf_dump_opts { + /* size of this struct, for backward/forward compatibility */ + size_t sz; + /* extra context passed to print callback */ void *ctx; + /* strip all the const/volatile/restrict mods */ + bool strip_mods; }; +#define btf_dump_opts__last_field strip_mods typedef void (*btf_dump_printf_fn_t)(void *ctx, const char *fmt, va_list args); diff --git a/tools/lib/bpf/btf_dump.c b/tools/lib/bpf/btf_dump.c index bbb430317260..4b843bbd8657 100644 --- a/tools/lib/bpf/btf_dump.c +++ b/tools/lib/bpf/btf_dump.c @@ -59,7 +59,8 @@ struct btf_dump { const struct btf *btf; const struct btf_ext *btf_ext; btf_dump_printf_fn_t printf_fn; - struct btf_dump_opts opts; + void *print_ctx; + bool strip_mods; /* per-type auxiliary state */ struct btf_dump_type_aux_state *type_states; @@ -115,7 +116,7 @@ static void btf_dump_printf(const struct btf_dump *d, const char *fmt, ...) va_list args; va_start(args, fmt); - d->printf_fn(d->opts.ctx, fmt, args); + d->printf_fn(d->print_ctx, fmt, args); va_end(args); } @@ -129,6 +130,9 @@ struct btf_dump *btf_dump__new(const struct btf *btf, struct btf_dump *d; int err; + if (!OPTS_VALID(opts, btf_dump_opts)) + return ERR_PTR(-EINVAL); + d = calloc(1, sizeof(struct btf_dump)); if (!d) return ERR_PTR(-ENOMEM); @@ -136,7 +140,8 @@ struct btf_dump *btf_dump__new(const struct btf *btf, d->btf = btf; d->btf_ext = btf_ext; d->printf_fn = printf_fn; - d->opts.ctx = opts ? opts->ctx : NULL; + d->print_ctx = OPTS_GET(opts, ctx, NULL); + d->strip_mods = OPTS_GET(opts, strip_mods, false); d->type_names = hashmap__new(str_hash_fn, str_equal_fn, NULL); if (IS_ERR(d->type_names)) { @@ -1045,6 +1050,10 @@ static void btf_dump_emit_type_decl(struct btf_dump *d, __u32 id, stack_start = d->decl_stack_cnt; for (;;) { + t = btf__type_by_id(d->btf, id); + if (d->strip_mods && btf_is_mod(t)) + goto skip_mod; + err = btf_dump_push_decl_stack_id(d, id); if (err < 0) { /* @@ -1056,12 +1065,11 @@ static void btf_dump_emit_type_decl(struct btf_dump *d, __u32 id, d->decl_stack_cnt = stack_start; return; } - +skip_mod: /* VOID */ if (id == 0) break; - t = btf__type_by_id(d->btf, id); switch (btf_kind(t)) { case BTF_KIND_PTR: case BTF_KIND_VOLATILE: From patchwork Wed Jul 1 06:45:24 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrii Nakryiko X-Patchwork-Id: 1320270 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=reject dis=none) header.from=fb.com Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=fb.com header.i=@fb.com header.a=rsa-sha256 header.s=facebook header.b=XmAjCk3v; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 49xWvQ3Ft3z9s1x for ; Wed, 1 Jul 2020 16:45:38 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727969AbgGAGph (ORCPT ); Wed, 1 Jul 2020 02:45:37 -0400 Received: from mx0a-00082601.pphosted.com ([67.231.145.42]:23568 "EHLO mx0a-00082601.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727888AbgGAGpg (ORCPT ); Wed, 1 Jul 2020 02:45:36 -0400 Received: from pps.filterd (m0044012.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 0616eZFf007317 for ; Tue, 30 Jun 2020 23:45:36 -0700 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fb.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding : content-type; s=facebook; bh=2L7S9U/k/EhDNpSC8L+eKX2Oid0O4l2yqewA+6LWDbc=; b=XmAjCk3vD538CRw1tmLaCtYg9cfSDNUSS5gd0SgGlOHcP7fZgoHz4E9YhwAE3pW5g1Cp mO/aX9oc5Xhi7s5b1k8xrzYoe8maEBO8dcfMjVNCI3h8vi3I2KNOrpfs4ld/6NlzDjmw DCfgVkYXWN56oYlI+IVfOSEY3+uwCB2jiOo= Received: from maileast.thefacebook.com ([163.114.130.16]) by mx0a-00082601.pphosted.com with ESMTP id 320bcdta0v-2 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Tue, 30 Jun 2020 23:45:36 -0700 Received: from intmgw001.03.ash8.facebook.com (2620:10d:c0a8:1b::d) by mail.thefacebook.com (2620:10d:c0a8:83::4) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1979.3; Tue, 30 Jun 2020 23:45:35 -0700 Received: by devbig012.ftw2.facebook.com (Postfix, from userid 137359) id 63FD82EC3A2B; Tue, 30 Jun 2020 23:45:33 -0700 (PDT) Smtp-Origin-Hostprefix: devbig From: Andrii Nakryiko Smtp-Origin-Hostname: devbig012.ftw2.facebook.com To: , , , CC: , , Andrii Nakryiko , Anton Protopopov Smtp-Origin-Cluster: ftw2c04 Subject: [PATCH bpf-next 2/3] selftests/bpf: add selftest testin btf_dump's mod-stripping output Date: Tue, 30 Jun 2020 23:45:24 -0700 Message-ID: <20200701064527.3158178-3-andriin@fb.com> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20200701064527.3158178-1-andriin@fb.com> References: <20200701064527.3158178-1-andriin@fb.com> MIME-Version: 1.0 X-FB-Internal: Safe X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.235,18.0.687 definitions=2020-07-01_03:2020-07-01,2020-07-01 signatures=0 X-Proofpoint-Spam-Details: rule=fb_default_notspam policy=fb_default score=0 mlxscore=0 lowpriorityscore=0 malwarescore=0 bulkscore=0 mlxlogscore=558 impostorscore=0 adultscore=0 cotscore=-2147483648 spamscore=0 suspectscore=9 phishscore=0 clxscore=1015 priorityscore=1501 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2004280000 definitions=main-2007010047 X-FB-Internal: deliver Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Add selftest validating that .strip_mods=true works. Signed-off-by: Andrii Nakryiko --- .../selftests/bpf/prog_tests/btf_dump.c | 5 +- .../bpf/progs/btf_dump_test_case_strip_mods.c | 50 +++++++++++++++++++ 2 files changed, 54 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/bpf/progs/btf_dump_test_case_strip_mods.c diff --git a/tools/testing/selftests/bpf/prog_tests/btf_dump.c b/tools/testing/selftests/bpf/prog_tests/btf_dump.c index cb33a7ee4e04..112b653b9c80 100644 --- a/tools/testing/selftests/bpf/prog_tests/btf_dump.c +++ b/tools/testing/selftests/bpf/prog_tests/btf_dump.c @@ -21,6 +21,8 @@ static struct btf_dump_test_case { {"btf_dump: bitfields", "btf_dump_test_case_bitfields", {}}, {"btf_dump: multidim", "btf_dump_test_case_multidim", {}}, {"btf_dump: namespacing", "btf_dump_test_case_namespacing", {}}, + {"btf_dump: strip mods", "btf_dump_test_case_strip_mods", + { .strip_mods = true }}, }; static int btf_dump_all_types(const struct btf *btf, @@ -125,6 +127,7 @@ void test_btf_dump() { if (!test__start_subtest(t->name)) continue; - test_btf_dump_case(i, &btf_dump_test_cases[i]); + t->opts.sz = sizeof(t->opts); + test_btf_dump_case(i, t); } } diff --git a/tools/testing/selftests/bpf/progs/btf_dump_test_case_strip_mods.c b/tools/testing/selftests/bpf/progs/btf_dump_test_case_strip_mods.c new file mode 100644 index 000000000000..1a6ba26d5d75 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/btf_dump_test_case_strip_mods.c @@ -0,0 +1,50 @@ +// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) +/* Copyright (c) 2020 Facebook */ + +struct s { + const int a; + volatile int * const b; + const volatile struct { + int * const volatile c1; + const int (* const c2)(volatile int x, const void * const y); + const volatile int c3[10]; + } c; + const union { + const int * restrict d1; + const volatile int * const volatile restrict d2; + } d[2]; + const struct { + const volatile int *e1[5]; + } e; + const volatile int * const * volatile * restrict *f; + const void * volatile * (*g)(const int x, const void * restrict y); +}; + +/* ----- START-EXPECTED-OUTPUT ----- */ +/* + *struct s { + * int a; + * int *b; + * struct { + * int *c1; + * int (*c2)(int, void *); + * int c3[10]; + * } c; + * union { + * int *d1; + * int *d2; + * } d[2]; + * struct { + * int *e1[5]; + * } e; + * int ****f; + * void ** (*g)(int, void *); + *}; + * + */ +/* ------ END-EXPECTED-OUTPUT ------ */ + +int f(struct s *s) +{ + return 0; +} From patchwork Wed Jul 1 06:45:26 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrii Nakryiko X-Patchwork-Id: 1320276 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Original-To: incoming-bpf@patchwork.ozlabs.org Delivered-To: patchwork-incoming-bpf@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=bpf-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=reject dis=none) header.from=fb.com Authentication-Results: ozlabs.org; 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s=facebook; bh=st9dicXue3nwPwPszDUQv4oirfmRwPAKDRm+vyeM0+A=; b=kbbMI/Cz2jbjkLW4EQukuV67JLVG+tc9duJXRY2JLYFdqXKoewQBDercYeWTwVvlPuMy mYk1khQJftaikWUs+GhvhD5AmJZFM+RvVenH2fz67rFaiE+qNwymQo1YA0KQtD6RqmEh ERL2/Bwdwn4t3aSDcrJbYB90OwfcuJ2DfwA= Received: from mail.thefacebook.com ([163.114.132.120]) by mx0a-00082601.pphosted.com with ESMTP id 31xp3rnwdm-2 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Tue, 30 Jun 2020 23:45:48 -0700 Received: from intmgw003.08.frc2.facebook.com (2620:10d:c085:208::11) by mail.thefacebook.com (2620:10d:c085:21d::4) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1979.3; Tue, 30 Jun 2020 23:45:47 -0700 Received: by devbig012.ftw2.facebook.com (Postfix, from userid 137359) id B34542EC3A2B; Tue, 30 Jun 2020 23:45:37 -0700 (PDT) Smtp-Origin-Hostprefix: devbig From: Andrii Nakryiko Smtp-Origin-Hostname: devbig012.ftw2.facebook.com To: , , , CC: , , Andrii Nakryiko , Anton Protopopov Smtp-Origin-Cluster: ftw2c04 Subject: [PATCH bpf-next 3/3] tools/bpftool: strip away modifiers from global variables Date: Tue, 30 Jun 2020 23:45:26 -0700 Message-ID: <20200701064527.3158178-5-andriin@fb.com> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20200701064527.3158178-1-andriin@fb.com> References: <20200701064527.3158178-1-andriin@fb.com> MIME-Version: 1.0 X-FB-Internal: Safe X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.235, 18.0.687 definitions=2020-07-01_03:2020-07-01,2020-07-01 signatures=0 X-Proofpoint-Spam-Details: rule=fb_default_notspam policy=fb_default score=0 mlxlogscore=829 adultscore=0 lowpriorityscore=0 mlxscore=0 malwarescore=0 bulkscore=0 phishscore=0 spamscore=0 priorityscore=1501 suspectscore=8 clxscore=1015 cotscore=-2147483648 impostorscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2004280000 definitions=main-2007010047 X-FB-Internal: deliver Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org Reliably remove all the type modifiers from global variable definitions, including cases of inner field const modifiers and arrays of const values. Also modify one of selftests to ensure that const volatile struct doesn't prevent user-space from modifying .rodata variable. Signed-off-by: Andrii Nakryiko --- tools/bpf/bpftool/gen.c | 13 ++++--------- tools/testing/selftests/bpf/prog_tests/skeleton.c | 6 +++--- tools/testing/selftests/bpf/progs/test_skeleton.c | 6 ++++-- 3 files changed, 11 insertions(+), 14 deletions(-) diff --git a/tools/bpf/bpftool/gen.c b/tools/bpf/bpftool/gen.c index 10de76b296ba..2a13114896c2 100644 --- a/tools/bpf/bpftool/gen.c +++ b/tools/bpf/bpftool/gen.c @@ -88,7 +88,7 @@ static const char *get_map_ident(const struct bpf_map *map) return NULL; } -static void codegen_btf_dump_printf(void *ct, const char *fmt, va_list args) +static void codegen_btf_dump_printf(void *ctx, const char *fmt, va_list args) { vprintf(fmt, args); } @@ -126,13 +126,6 @@ static int codegen_datasec_def(struct bpf_object *obj, ); int need_off = sec_var->offset, align_off, align; __u32 var_type_id = var->type; - const struct btf_type *t; - - t = btf__type_by_id(btf, var_type_id); - while (btf_is_mod(t)) { - var_type_id = t->type; - t = btf__type_by_id(btf, var_type_id); - } if (off > need_off) { p_err("Something is wrong for %s's variable #%d: need offset %d, already at %d.\n", @@ -176,12 +169,14 @@ static int codegen_datasec_def(struct bpf_object *obj, static int codegen_datasecs(struct bpf_object *obj, const char *obj_name) { + /* strip out const/volatile/restrict modifiers for datasecs */ + DECLARE_LIBBPF_OPTS(btf_dump_opts, opts, .strip_mods = true); struct btf *btf = bpf_object__btf(obj); int n = btf__get_nr_types(btf); struct btf_dump *d; int i, err = 0; - d = btf_dump__new(btf, NULL, NULL, codegen_btf_dump_printf); + d = btf_dump__new(btf, NULL, &opts, codegen_btf_dump_printf); if (IS_ERR(d)) return PTR_ERR(d); diff --git a/tools/testing/selftests/bpf/prog_tests/skeleton.c b/tools/testing/selftests/bpf/prog_tests/skeleton.c index fa153cf67b1b..fe87b77af459 100644 --- a/tools/testing/selftests/bpf/prog_tests/skeleton.c +++ b/tools/testing/selftests/bpf/prog_tests/skeleton.c @@ -41,7 +41,7 @@ void test_skeleton(void) CHECK(bss->in4 != 0, "in4", "got %lld != exp %lld\n", bss->in4, 0LL); CHECK(bss->out4 != 0, "out4", "got %lld != exp %lld\n", bss->out4, 0LL); - CHECK(rodata->in6 != 0, "in6", "got %d != exp %d\n", rodata->in6, 0); + CHECK(rodata->in.in6 != 0, "in6", "got %d != exp %d\n", rodata->in.in6, 0); CHECK(bss->out6 != 0, "out6", "got %d != exp %d\n", bss->out6, 0); /* validate we can pre-setup global variables, even in .bss */ @@ -49,7 +49,7 @@ void test_skeleton(void) data->in2 = 11; bss->in3 = 12; bss->in4 = 13; - rodata->in6 = 14; + rodata->in.in6 = 14; err = test_skeleton__load(skel); if (CHECK(err, "skel_load", "failed to load skeleton: %d\n", err)) @@ -60,7 +60,7 @@ void test_skeleton(void) CHECK(data->in2 != 11, "in2", "got %lld != exp %lld\n", data->in2, 11LL); CHECK(bss->in3 != 12, "in3", "got %d != exp %d\n", bss->in3, 12); CHECK(bss->in4 != 13, "in4", "got %lld != exp %lld\n", bss->in4, 13LL); - CHECK(rodata->in6 != 14, "in6", "got %d != exp %d\n", rodata->in6, 14); + CHECK(rodata->in.in6 != 14, "in6", "got %d != exp %d\n", rodata->in.in6, 14); /* now set new values and attach to get them into outX variables */ data->in1 = 1; diff --git a/tools/testing/selftests/bpf/progs/test_skeleton.c b/tools/testing/selftests/bpf/progs/test_skeleton.c index 77ae86f44db5..374ccef704e1 100644 --- a/tools/testing/selftests/bpf/progs/test_skeleton.c +++ b/tools/testing/selftests/bpf/progs/test_skeleton.c @@ -20,7 +20,9 @@ long long in4 __attribute__((aligned(64))) = 0; struct s in5 = {}; /* .rodata section */ -const volatile int in6 = 0; +const volatile struct { + const int in6; +} in = {}; /* .data section */ int out1 = -1; @@ -46,7 +48,7 @@ int handler(const void *ctx) out3 = in3; out4 = in4; out5 = in5; - out6 = in6; + out6 = in.in6; bpf_syscall = CONFIG_BPF_SYSCALL; kern_ver = LINUX_KERNEL_VERSION;