From patchwork Fri Nov 24 11:30:33 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hou Tao X-Patchwork-Id: 13467562 X-Patchwork-Delegate: bpf@iogearbox.net Authentication-Results: smtp.subspace.kernel.org; dkim=none Received: from dggsgout11.his.huawei.com (dggsgout11.his.huawei.com [45.249.212.51]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8B49710EB for ; Fri, 24 Nov 2023 03:29:35 -0800 (PST) Received: from mail.maildlp.com (unknown [172.19.93.142]) by dggsgout11.his.huawei.com (SkyGuard) with ESMTP id 4ScCS86FdSz4f3jZ6 for ; Fri, 24 Nov 2023 19:29:28 +0800 (CST) Received: from mail02.huawei.com (unknown [10.116.40.112]) by mail.maildlp.com (Postfix) with ESMTP id 9E09A1A06DC for ; Fri, 24 Nov 2023 19:29:31 +0800 (CST) Received: from huaweicloud.com (unknown [10.175.124.27]) by APP1 (Coremail) with SMTP id cCh0CgDn6xEUiWBloME3Bw--.31197S10; Fri, 24 Nov 2023 19:29:31 +0800 (CST) From: Hou Tao To: bpf@vger.kernel.org Cc: Martin KaFai Lau , Alexei Starovoitov , Andrii Nakryiko , Song Liu , Hao Luo , Yonghong Song , Daniel Borkmann , KP Singh , Stanislav Fomichev , Jiri Olsa , John Fastabend , houtao1@huawei.com Subject: [PATCH bpf v3 6/6] selftests/bpf: Test outer map update operations in syscall program Date: Fri, 24 Nov 2023 19:30:33 +0800 Message-Id: <20231124113033.503338-7-houtao@huaweicloud.com> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20231124113033.503338-1-houtao@huaweicloud.com> References: <20231124113033.503338-1-houtao@huaweicloud.com> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-CM-TRANSID: cCh0CgDn6xEUiWBloME3Bw--.31197S10 X-Coremail-Antispam: 1UD129KBjvJXoW3WF4kXr1kJFW7KryxtF17Awb_yoW7Kry8pa yrGa4UtF4rXF43Gry8Xa17WayfKF1vg343trsrtw1YvFnrXr1SqFyIgay7tF13WrZ3Zr4F vay7trZ5Aw4UZFDanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUBIb4IE77IF4wAFF20E14v26rWj6s0DM7CY07I20VC2zVCF04k2 6cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28IrcIa0xkI8VA2jI8067AKxVWUAV Cq3wA2048vs2IY020Ec7CjxVAFwI0_Xr0E3s1l8cAvFVAK0II2c7xJM28CjxkF64kEwVA0 rcxSw2x7M28EF7xvwVC0I7IYx2IY67AKxVW7JVWDJwA2z4x0Y4vE2Ix0cI8IcVCY1x0267 AKxVW8Jr0_Cr1UM28EF7xvwVC2z280aVAFwI0_GcCE3s1l84ACjcxK6I8E87Iv6xkF7I0E 14v26rxl6s0DM2AIxVAIcxkEcVAq07x20xvEncxIr21l5I8CrVACY4xI64kE6c02F40Ex7 xfMcIj6xIIjxv20xvE14v26r1j6r18McIj6I8E87Iv67AKxVWUJVW8JwAm72CE4IkC6x0Y z7v_Jr0_Gr1lF7xvr2IYc2Ij64vIr41lFIxGxcIEc7CjxVA2Y2ka0xkIwI1l42xK82IYc2 Ij64vIr41l4I8I3I0E4IkC6x0Yz7v_Jr0_Gr1lx2IqxVAqx4xG67AKxVWUJVWUGwC20s02 6x8GjcxK67AKxVWUGVWUWwC2zVAF1VAY17CE14v26r1q6r43MIIYrxkI7VAKI48JMIIF0x vE2Ix0cI8IcVAFwI0_JFI_Gr1lIxAIcVC0I7IYx2IY6xkF7I0E14v26F4j6r4UJwCI42IY 6xAIw20EY4v20xvaj40_Jr0_JF4lIxAIcVC2z280aVAFwI0_Jr0_Gr1lIxAIcVC2z280aV CY1x0267AKxVW8JVW8JrUvcSsGvfC2KfnxnUUI43ZEXa7IU13l1DUUUUU== X-CM-SenderInfo: xkrx3t3r6k3tpzhluzxrxghudrp/ X-Patchwork-Delegate: bpf@iogearbox.net From: Hou Tao Syscall program is running with rcu_read_lock_trace being held, so if bpf_map_update_elem() or bpf_map_delete_elem() invokes synchronize_rcu_tasks_trace() when operating on an outer map, there will be dead-lock, so add a test to guarantee that it is dead-lock free. Signed-off-by: Hou Tao --- .../selftests/bpf/prog_tests/syscall.c | 30 +++++- tools/testing/selftests/bpf/progs/syscall.c | 91 ++++++++++++++++++- 2 files changed, 114 insertions(+), 7 deletions(-) diff --git a/tools/testing/selftests/bpf/prog_tests/syscall.c b/tools/testing/selftests/bpf/prog_tests/syscall.c index f4d40001155a..0be8301c0ffd 100644 --- a/tools/testing/selftests/bpf/prog_tests/syscall.c +++ b/tools/testing/selftests/bpf/prog_tests/syscall.c @@ -12,7 +12,7 @@ struct args { int btf_fd; }; -void test_syscall(void) +static void test_syscall_load_prog(void) { static char verifier_log[8192]; struct args ctx = { @@ -32,7 +32,7 @@ void test_syscall(void) if (!ASSERT_OK_PTR(skel, "skel_load")) goto cleanup; - prog_fd = bpf_program__fd(skel->progs.bpf_prog); + prog_fd = bpf_program__fd(skel->progs.load_prog); err = bpf_prog_test_run_opts(prog_fd, &tattr); ASSERT_EQ(err, 0, "err"); ASSERT_EQ(tattr.retval, 1, "retval"); @@ -53,3 +53,29 @@ void test_syscall(void) if (ctx.btf_fd > 0) close(ctx.btf_fd); } + +static void test_syscall_update_outer_map(void) +{ + LIBBPF_OPTS(bpf_test_run_opts, opts); + struct syscall *skel; + int err, prog_fd; + + skel = syscall__open_and_load(); + if (!ASSERT_OK_PTR(skel, "skel_load")) + goto cleanup; + + prog_fd = bpf_program__fd(skel->progs.update_outer_map); + err = bpf_prog_test_run_opts(prog_fd, &opts); + ASSERT_EQ(err, 0, "err"); + ASSERT_EQ(opts.retval, 1, "retval"); +cleanup: + syscall__destroy(skel); +} + +void test_syscall(void) +{ + if (test__start_subtest("load_prog")) + test_syscall_load_prog(); + if (test__start_subtest("update_outer_map")) + test_syscall_update_outer_map(); +} diff --git a/tools/testing/selftests/bpf/progs/syscall.c b/tools/testing/selftests/bpf/progs/syscall.c index e550f728962d..23058abbaabd 100644 --- a/tools/testing/selftests/bpf/progs/syscall.c +++ b/tools/testing/selftests/bpf/progs/syscall.c @@ -6,9 +6,15 @@ #include #include <../../../tools/include/linux/filter.h> #include +#include +#include char _license[] SEC("license") = "GPL"; +struct bpf_map { + int id; +} __attribute__((preserve_access_index)); + struct args { __u64 log_buf; __u32 log_size; @@ -27,6 +33,32 @@ struct args { BTF_TYPE_ENC(name, BTF_INFO_ENC(BTF_KIND_INT, 0, 0), sz), \ BTF_INT_ENC(encoding, bits_offset, bits) +struct { + __uint(type, BPF_MAP_TYPE_ARRAY); + __type(key, int); + __type(value, union bpf_attr); + __uint(max_entries, 1); +} bpf_attr_array SEC(".maps"); + +struct inner_map_type { + __uint(type, BPF_MAP_TYPE_ARRAY); + __uint(key_size, 4); + __uint(value_size, 4); + __uint(max_entries, 1); +} inner_map SEC(".maps"); + +struct { + __uint(type, BPF_MAP_TYPE_ARRAY_OF_MAPS); + __type(key, int); + __type(value, int); + __uint(max_entries, 1); + __array(values, struct inner_map_type); +} outer_array_map SEC(".maps") = { + .values = { + [0] = &inner_map, + }, +}; + static int btf_load(void) { struct btf_blob { @@ -58,7 +90,7 @@ static int btf_load(void) } SEC("syscall") -int bpf_prog(struct args *ctx) +int load_prog(struct args *ctx) { static char license[] = "GPL"; static struct bpf_insn insns[] = { @@ -94,8 +126,8 @@ int bpf_prog(struct args *ctx) map_create_attr.max_entries = ctx->max_entries; map_create_attr.btf_fd = ret; - prog_load_attr.license = (long) license; - prog_load_attr.insns = (long) insns; + prog_load_attr.license = (unsigned long)license; + prog_load_attr.insns = (unsigned long)insns; prog_load_attr.log_buf = ctx->log_buf; prog_load_attr.log_size = ctx->log_size; prog_load_attr.log_level = 1; @@ -107,8 +139,8 @@ int bpf_prog(struct args *ctx) insns[3].imm = ret; map_update_attr.map_fd = ret; - map_update_attr.key = (long) &key; - map_update_attr.value = (long) &value; + map_update_attr.key = (unsigned long)&key; + map_update_attr.value = (unsigned long)&value; ret = bpf_sys_bpf(BPF_MAP_UPDATE_ELEM, &map_update_attr, sizeof(map_update_attr)); if (ret < 0) return ret; @@ -119,3 +151,52 @@ int bpf_prog(struct args *ctx) ctx->prog_fd = ret; return 1; } + +SEC("syscall") +int update_outer_map(void *ctx) +{ + int zero = 0, ret = 0, outer_fd = -1, inner_fd = -1, err; + const int attr_sz = sizeof(union bpf_attr); + union bpf_attr *attr; + + attr = bpf_map_lookup_elem((struct bpf_map *)&bpf_attr_array, &zero); + if (!attr) + goto out; + + memset(attr, 0, attr_sz); + attr->map_id = ((struct bpf_map *)&outer_array_map)->id; + outer_fd = bpf_sys_bpf(BPF_MAP_GET_FD_BY_ID, attr, attr_sz); + if (outer_fd < 0) + goto out; + + memset(attr, 0, attr_sz); + attr->map_type = BPF_MAP_TYPE_ARRAY; + attr->key_size = 4; + attr->value_size = 4; + attr->max_entries = 1; + inner_fd = bpf_sys_bpf(BPF_MAP_CREATE, attr, attr_sz); + if (inner_fd < 0) + goto out; + + memset(attr, 0, attr_sz); + attr->map_fd = outer_fd; + attr->key = (unsigned long)&zero; + attr->value = (unsigned long)&inner_fd; + err = bpf_sys_bpf(BPF_MAP_UPDATE_ELEM, attr, attr_sz); + if (err) + goto out; + + memset(attr, 0, attr_sz); + attr->map_fd = outer_fd; + attr->key = (unsigned long)&zero; + err = bpf_sys_bpf(BPF_MAP_DELETE_ELEM, attr, attr_sz); + if (err) + goto out; + ret = 1; +out: + if (inner_fd >= 0) + bpf_sys_close(inner_fd); + if (outer_fd >= 0) + bpf_sys_close(outer_fd); + return ret; +}