From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3759724E4AF; Mon, 16 Mar 2026 07:56:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773647761; cv=none; b=UchspKIwJfodKbr1Fxh/8+6mknp8KlZYYvabxaIyGM6HzaRiIR8OQA1cYOeogYIX8wr1z2kd0Fc3aQVxSmfolpQ+jaR3vRY69oXZ43Hn3Lhtn6U11aJjuU4nvPwA1IQir1wNgo9zVssvc8gFQ8ugOZ3PndqLotnRGDIIOFzTkgs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773647761; c=relaxed/simple; bh=VNLtn0O687UCjYGu3w++0zZM6yOLA52+O4k8GjVm6BY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=I9zqqDz5vgzm3tIVXEBQIvKcecMd+0YqHkK3OfVL2UOuThNuu5sMnI/VKp9PYvG8fxvPrX8NqU61fECFPhBhwj/PxgKvE+gTqSZCPukpNswYCKFxwXkcGRts86uPAx0uecj12ZHz138k3U15eZ7iimQZJ15B+1QTMABHRIUbH0U= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=cXt9ZpOA; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="cXt9ZpOA" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 42232C19421; Mon, 16 Mar 2026 07:55:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1773647761; bh=VNLtn0O687UCjYGu3w++0zZM6yOLA52+O4k8GjVm6BY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=cXt9ZpOAwB7oetPinaW28IzsP0cMNRldCprXmcoeQxPvH7kSLxoAgWH8Fq0oSve4N qkmOk/Gac9PfLQAQ03eru+FEjpbyI3bUim1ihqwW3MP6CKVlAtqQwD3ua0d3nnB8F+ fY23GEVKBAU9uJPxqTBXN3azLcIXk1cMw4nqa6wy1+sv8OOAns2ekoUDIac1wkLR+8 Do6H7aKtCY3osttNoDtbtJ9EDAzX44362f/YGx93EhAozDklz7pJT3iEIZ1tRr2/26 q5onOzmF+bBi5RNZ8PKPNtwW+59PmdtVR9TWsuwmeGN+wdXSo3ZfMXvPAplZ9NmHeC lKu/xcyxofbUg== From: Jiri Olsa To: Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko Cc: bpf@vger.kernel.org, linux-trace-kernel@vger.kernel.org, Martin KaFai Lau , Eduard Zingerman , Song Liu , Yonghong Song , Menglong Dong , Steven Rostedt Subject: [PATCHv3 bpf-next 24/24] selftests/bpf: Add tracing multi attach rollback tests Date: Mon, 16 Mar 2026 08:51:38 +0100 Message-ID: <20260316075138.465430-25-jolsa@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260316075138.465430-1-jolsa@kernel.org> References: <20260316075138.465430-1-jolsa@kernel.org> Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Adding tests for the rollback code when the tracing_multi link won't get attached, covering 2 reasons: - wrong btf id passed by user, where all previously allocated trampolines will be released - trampoline for requested function is fully attached (has already maximum programs attached) and the link fails, the rollback code needs to release all previously link-ed trampolines and release them We need the bpf_fentry_test* unattached for the tests to pass, so the rollback tests are serial. Signed-off-by: Jiri Olsa --- .../selftests/bpf/prog_tests/tracing_multi.c | 181 ++++++++++++++++++ .../bpf/progs/tracing_multi_rollback.c | 38 ++++ 2 files changed, 219 insertions(+) create mode 100644 tools/testing/selftests/bpf/progs/tracing_multi_rollback.c diff --git a/tools/testing/selftests/bpf/prog_tests/tracing_multi.c b/tools/testing/selftests/bpf/prog_tests/tracing_multi.c index a0fcda51bb6c..10b8cc6b368b 100644 --- a/tools/testing/selftests/bpf/prog_tests/tracing_multi.c +++ b/tools/testing/selftests/bpf/prog_tests/tracing_multi.c @@ -10,6 +10,7 @@ #include "tracing_multi_session.skel.h" #include "tracing_multi_fail.skel.h" #include "tracing_multi_bench.skel.h" +#include "tracing_multi_rollback.skel.h" #include "trace_helpers.h" static __u64 bpf_fentry_test_cookies[] = { @@ -649,6 +650,186 @@ void serial_test_tracing_multi_bench_attach(void) free(ids); } +static void tracing_multi_rollback_run(struct tracing_multi_rollback *skel) +{ + LIBBPF_OPTS(bpf_test_run_opts, topts); + int err, prog_fd; + + prog_fd = bpf_program__fd(skel->progs.test_fentry); + err = bpf_prog_test_run_opts(prog_fd, &topts); + ASSERT_OK(err, "test_run"); + + /* make sure the rollback code did not leave any program attached */ + ASSERT_EQ(skel->bss->test_result_fentry, 0, "test_result_fentry"); + ASSERT_EQ(skel->bss->test_result_fexit, 0, "test_result_fexit"); +} + +static void test_rollback_put(void) +{ + LIBBPF_OPTS(bpf_tracing_multi_opts, opts); + struct tracing_multi_rollback *skel = NULL; + size_t cnt = FUNCS_CNT; + __u32 *ids = NULL; + int err; + + skel = tracing_multi_rollback__open(); + if (!ASSERT_OK_PTR(skel, "tracing_multi_rollback__open")) + return; + + bpf_program__set_autoload(skel->progs.test_fentry, true); + bpf_program__set_autoload(skel->progs.test_fexit, true); + + err = tracing_multi_rollback__load(skel); + if (!ASSERT_OK(err, "tracing_multi_rollback__load")) + goto cleanup; + + ids = get_ids(bpf_fentry_test, cnt, NULL); + if (!ASSERT_OK_PTR(ids, "get_ids")) + goto cleanup; + + /* + * Mangle last id to trigger rollback, which needs to do put + * on get-ed trampolines. + */ + ids[9] = 0; + + opts.ids = ids; + opts.cnt = cnt; + + skel->bss->pid = getpid(); + + skel->links.test_fentry = bpf_program__attach_tracing_multi(skel->progs.test_fentry, + NULL, &opts); + if (!ASSERT_ERR_PTR(skel->links.test_fentry, "bpf_program__attach_tracing_multi")) + goto cleanup; + + skel->links.test_fexit = bpf_program__attach_tracing_multi(skel->progs.test_fexit, + NULL, &opts); + if (!ASSERT_ERR_PTR(skel->links.test_fexit, "bpf_program__attach_tracing_multi")) + goto cleanup; + + /* We don't really attach any program, but let's make sure. */ + tracing_multi_rollback_run(skel); + +cleanup: + tracing_multi_rollback__destroy(skel); + free(ids); +} + + +static void fillers_cleanup(struct tracing_multi_rollback **skels, int cnt) +{ + int i; + + for (i = 0; i < cnt; i++) + tracing_multi_rollback__destroy(skels[i]); + + free(skels); +} + +static struct tracing_multi_rollback **fillers_load_and_link(int max) +{ + struct tracing_multi_rollback **skels, *skel; + int i, err; + + skels = calloc(max + 1, sizeof(*skels)); + if (!ASSERT_OK_PTR(skels, "calloc")) + return NULL; + + for (i = 0; i < max; i++) { + skel = skels[i] = tracing_multi_rollback__open(); + if (!ASSERT_OK_PTR(skels[i], "tracing_multi_rollback__open")) + goto cleanup; + + bpf_program__set_autoload(skel->progs.filler, true); + + err = tracing_multi_rollback__load(skel); + if (!ASSERT_OK(err, "tracing_multi_rollback__load")) + goto cleanup; + + skel->links.filler = bpf_program__attach_trace(skel->progs.filler); + if (!ASSERT_OK_PTR(skels[i]->links.filler, "bpf_program__attach_trace")) + goto cleanup; + } + + return skels; + +cleanup: + fillers_cleanup(skels, i); + return NULL; +} + +static void test_rollback_unlink(void) +{ + LIBBPF_OPTS(bpf_tracing_multi_opts, opts); + struct tracing_multi_rollback **fillers; + struct tracing_multi_rollback *skel; + size_t cnt = FUNCS_CNT; + __u32 *ids = NULL; + int err, max; + + max = get_bpf_max_tramp_links(); + if (!ASSERT_GE(max, 1, "bpf_max_tramp_links")) + return; + + /* Attach maximum allowed programs to bpf_fentry_test10 */ + fillers = fillers_load_and_link(max); + if (!ASSERT_OK_PTR(fillers, "fillers_load_and_link")) + return; + + skel = tracing_multi_rollback__open(); + if (!ASSERT_OK_PTR(skel, "tracing_multi_rollback__open")) + goto cleanup; + + bpf_program__set_autoload(skel->progs.test_fentry, true); + bpf_program__set_autoload(skel->progs.test_fexit, true); + + /* + * Attach tracing_multi link on bpf_fentry_test1-10, which will + * fail on bpf_fentry_test10 function, because it already has + * maximum allowed programs attached. + * + * The rollback needs to unlink already link-ed trampolines and + * put all of them. + */ + err = tracing_multi_rollback__load(skel); + if (!ASSERT_OK(err, "tracing_multi_rollback__load")) + goto cleanup; + + ids = get_ids(bpf_fentry_test, cnt, NULL); + if (!ASSERT_OK_PTR(ids, "get_ids")) + goto cleanup; + + opts.ids = ids; + opts.cnt = cnt; + + skel->bss->pid = getpid(); + + skel->links.test_fentry = bpf_program__attach_tracing_multi(skel->progs.test_fentry, + NULL, &opts); + if (!ASSERT_ERR_PTR(skel->links.test_fentry, "bpf_program__attach_tracing_multi")) + goto cleanup; + + skel->links.test_fexit = bpf_program__attach_tracing_multi(skel->progs.test_fexit, + NULL, &opts); + if (!ASSERT_ERR_PTR(skel->links.test_fexit, "bpf_program__attach_tracing_multi")) + goto cleanup; + + tracing_multi_rollback_run(skel); + +cleanup: + fillers_cleanup(fillers, max); + free(ids); +} + +void serial_test_tracing_multi_attach_rollback(void) +{ + if (test__start_subtest("put")) + test_rollback_put(); + if (test__start_subtest("unlink")) + test_rollback_unlink(); +} + void test_tracing_multi_test(void) { #ifndef __x86_64__ diff --git a/tools/testing/selftests/bpf/progs/tracing_multi_rollback.c b/tools/testing/selftests/bpf/progs/tracing_multi_rollback.c new file mode 100644 index 000000000000..eb27869f551a --- /dev/null +++ b/tools/testing/selftests/bpf/progs/tracing_multi_rollback.c @@ -0,0 +1,38 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include +#include +#include + +char _license[] SEC("license") = "GPL"; + +int pid = 0; + +__u64 test_result_fentry = 0; +__u64 test_result_fexit = 0; + +SEC("?fentry.multi") +int BPF_PROG(test_fentry) +{ + if (bpf_get_current_pid_tgid() >> 32 != pid) + return 0; + + test_result_fentry++; + return 0; +} + +SEC("?fexit.multi") +int BPF_PROG(test_fexit) +{ + if (bpf_get_current_pid_tgid() >> 32 != pid) + return 0; + + test_result_fexit++; + return 0; +} + +SEC("?fentry/bpf_fentry_test10") +int BPF_PROG(filler) +{ + return 0; +} -- 2.53.0