From patchwork Tue Sep 3 22:59:54 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yonghong Song X-Patchwork-Id: 13789492 X-Patchwork-Delegate: bpf@iogearbox.net Received: from 69-171-232-180.mail-mxout.facebook.com (69-171-232-180.mail-mxout.facebook.com [69.171.232.180]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 39B281D58B3 for ; Tue, 3 Sep 2024 23:00:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=69.171.232.180 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725404409; cv=none; b=gLAHJWSkrCzlBCDxcfBgiqEHmWzlFtBREs6hZkZaMMh0kAi8gp6BEl93xtpaMYFgKwwZEQSauSTyLyUwGLC9s2yz+KjMhKmKz7ZAO8fBttbb0eyOdqvITtCyKSzs+fW9V4A9dc4ZAg/En6LYgFBPgSjtnQOlZE0NkAB5D80HBis= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725404409; c=relaxed/simple; bh=BzolBEPaYQuDJK8cyLRmuL22aoQeq97Z56FyDLPUMcE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Z/8g93DrlItHcXGvKmN+3QZqEX3SKDKB01U0Wlg1YP5pZNL5vV3Rzct63NbK+HftjecaRQ/1+czrb0LaFEtoLlJqJqHkC4abwb07w622bFAdwvSkTk2Mr78ZXG+S5UGnfBqSOjZ7YYMJoAVx4uKdclRv89FFQ68IK2JJo+nokk8= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.dev; spf=fail smtp.mailfrom=linux.dev; arc=none smtp.client-ip=69.171.232.180 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=fail smtp.mailfrom=linux.dev Received: by devbig309.ftw3.facebook.com (Postfix, from userid 128203) id DA08F88DE24B; Tue, 3 Sep 2024 15:59:54 -0700 (PDT) From: Yonghong Song To: bpf@vger.kernel.org Cc: Alexei Starovoitov , Andrii Nakryiko , Daniel Borkmann , kernel-team@fb.com, Martin KaFai Lau Subject: [PATCH bpf-next v2 2/2] selftests/bpf: Add a selftest for x86 jit convergence issues Date: Tue, 3 Sep 2024 15:59:54 -0700 Message-ID: <20240903225954.2066646-1-yonghong.song@linux.dev> X-Mailer: git-send-email 2.43.5 In-Reply-To: <20240903225949.2066234-1-yonghong.song@linux.dev> References: <20240903225949.2066234-1-yonghong.song@linux.dev> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Patchwork-Delegate: bpf@iogearbox.net The core part of the selftest, i.e., the je <-> jmp cycle, mimics the original sched-ext bpf program. The test will fail without the previous patch. I tried to create some cases for other potential cycles (je <-> je, jmp <-> je and jmp <-> jmp) with similar pattern to the test in this patch, but failed. So this patch only contains one test for je <-> jmp cycle. Signed-off-by: Yonghong Song --- .../selftests/bpf/prog_tests/verifier.c | 2 + .../bpf/progs/verifier_jit_convergence.c | 128 ++++++++++++++++++ 2 files changed, 130 insertions(+) create mode 100644 tools/testing/selftests/bpf/progs/verifier_jit_convergence.c diff --git a/tools/testing/selftests/bpf/prog_tests/verifier.c b/tools/testing/selftests/bpf/prog_tests/verifier.c index 80a90c627182..df398e714dff 100644 --- a/tools/testing/selftests/bpf/prog_tests/verifier.c +++ b/tools/testing/selftests/bpf/prog_tests/verifier.c @@ -39,6 +39,7 @@ #include "verifier_int_ptr.skel.h" #include "verifier_iterating_callbacks.skel.h" #include "verifier_jeq_infer_not_null.skel.h" +#include "verifier_jit_convergence.skel.h" #include "verifier_ld_ind.skel.h" #include "verifier_ldsx.skel.h" #include "verifier_leak_ptr.skel.h" @@ -163,6 +164,7 @@ void test_verifier_helper_value_access(void) { RUN(verifier_helper_value_access void test_verifier_int_ptr(void) { RUN(verifier_int_ptr); } void test_verifier_iterating_callbacks(void) { RUN(verifier_iterating_callbacks); } void test_verifier_jeq_infer_not_null(void) { RUN(verifier_jeq_infer_not_null); } +void test_verifier_jit_convergence(void) { RUN(verifier_jit_convergence); } void test_verifier_ld_ind(void) { RUN(verifier_ld_ind); } void test_verifier_ldsx(void) { RUN(verifier_ldsx); } void test_verifier_leak_ptr(void) { RUN(verifier_leak_ptr); } diff --git a/tools/testing/selftests/bpf/progs/verifier_jit_convergence.c b/tools/testing/selftests/bpf/progs/verifier_jit_convergence.c new file mode 100644 index 000000000000..fdc4ccc83c7d --- /dev/null +++ b/tools/testing/selftests/bpf/progs/verifier_jit_convergence.c @@ -0,0 +1,128 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2024 Meta Platforms, Inc. and affiliates. */ + +#include +#include +#include "bpf_misc.h" + +#if defined(__TARGET_ARCH_x86) + +struct value_t { + long long a[32]; +}; + +struct { + __uint(type, BPF_MAP_TYPE_HASH); + __uint(max_entries, 1); + __type(key, long long); + __type(value, struct value_t); +} map_hash SEC(".maps"); + +SEC("socket") +__description("bpf_jit_convergence je <-> jmp") +__success __retval(0) +__arch_x86_64 +__jited(" pushq %rbp") +__naked void btf_jit_convergence_je_jmp(void) +{ + asm volatile ( + "call %[bpf_get_prandom_u32];" + "if r0 == 0 goto l20_%=;" + "if r0 == 1 goto l21_%=;" + "if r0 == 2 goto l22_%=;" + "if r0 == 3 goto l23_%=;" + "if r0 == 4 goto l24_%=;" + "call %[bpf_get_prandom_u32];" + "call %[bpf_get_prandom_u32];" +"l20_%=:" +"l21_%=:" +"l22_%=:" +"l23_%=:" +"l24_%=:" + "r1 = 0;" + "*(u64 *)(r10 - 8) = r1;" + "r2 = r10;" + "r2 += -8;" + "r1 = %[map_hash] ll;" + "call %[bpf_map_lookup_elem];" + "if r0 == 0 goto l1_%=;" + "r6 = r0;" + "call %[bpf_get_prandom_u32];" + "r7 = r0;" + "r5 = r6;" + "if r0 != 0x0 goto l12_%=;" + "call %[bpf_get_prandom_u32];" + "r1 = r0;" + "r2 = r6;" + "if r1 == 0x0 goto l0_%=;" +"l9_%=:" + "r2 = *(u64 *)(r6 + 0x0);" + "r2 += 0x1;" + "*(u64 *)(r6 + 0x0) = r2;" + "goto l1_%=;" +"l12_%=:" + "r1 = r7;" + "r1 += 0x98;" + "r2 = r5;" + "r2 += 0x90;" + "r2 = *(u32 *)(r2 + 0x0);" + "r3 = r7;" + "r3 &= 0x1;" + "r2 *= 0xa8;" + "if r3 == 0x0 goto l2_%=;" + "r1 += r2;" + "r1 -= r7;" + "r1 += 0x8;" + "if r1 <= 0xb20 goto l3_%=;" + "r1 = 0x0;" + "goto l4_%=;" +"l3_%=:" + "r1 += r7;" +"l4_%=:" + "if r1 == 0x0 goto l8_%=;" + "goto l9_%=;" +"l2_%=:" + "r1 += r2;" + "r1 -= r7;" + "r1 += 0x10;" + "if r1 <= 0xb20 goto l6_%=;" + "r1 = 0x0;" + "goto l7_%=;" +"l6_%=:" + "r1 += r7;" +"l7_%=:" + "if r1 == 0x0 goto l8_%=;" + "goto l9_%=;" +"l0_%=:" + "r1 = 0x3;" + "*(u64 *)(r10 - 0x10) = r1;" + "r2 = r1;" + "goto l1_%=;" +"l8_%=:" + "r1 = r5;" + "r1 += 0x4;" + "r1 = *(u32 *)(r1 + 0x0);" + "*(u64 *)(r10 - 0x8) = r1;" +"l1_%=:" + "r0 = 0;" + "exit;" + : + : __imm(bpf_get_prandom_u32), + __imm(bpf_map_lookup_elem), + __imm_addr(map_hash) + : __clobber_all); +} + +#else + +SEC("socket") +__description("non-x86 has no jit convergence issue, use a dummy test") +__success +int dummy_test(void) +{ + return 0; +} + +#endif + +char _license[] SEC("license") = "GPL";