From 898f55f50a00f56dac1ef55f5478c10a7511d0a6 Mon Sep 17 00:00:00 2001 From: Eduard Zingerman Date: Tue, 8 Aug 2023 19:27:55 +0300 Subject: [PATCH] selftests/bpf: relax expected log messages to allow emitting BPF_ST Update [1] to LLVM BPF backend seeks to enable generation of BPF_ST instruction when CPUv4 is selected. This affects expected log messages for the following selftests: - log_fixup/missing_map - spin_lock/lock_id_mapval_preserve - spin_lock/lock_id_innermapval_preserve Expected messages in these tests hard-code instruction numbers for BPF programs compiled from C. These instruction numbers change when BPF_ST is allowed because single BPF_ST instruction replaces a pair of BPF_MOV/BPF_STX instructions, e.g.: r1 = 42; *(u32 *)(r10 - 8) = r1; ---> *(u32 *)(r10 - 8) = 42; This commit updates expected log messages to avoid matching specific instruction numbers (program position still could be uniquely identified). [1] https://reviews.llvm.org/D140804 "[BPF] support for BPF_ST instruction in codegen" Signed-off-by: Eduard Zingerman Acked-by: Yonghong Song Link: https://lore.kernel.org/r/20230808162755.392606-1-eddyz87@gmail.com Signed-off-by: Martin KaFai Lau --- .../selftests/bpf/prog_tests/log_fixup.c | 2 +- .../selftests/bpf/prog_tests/spin_lock.c | 37 ++++++++++++++++--- 2 files changed, 33 insertions(+), 6 deletions(-) diff --git a/tools/testing/selftests/bpf/prog_tests/log_fixup.c b/tools/testing/selftests/bpf/prog_tests/log_fixup.c index dba71d98a227..effd78b2a657 100644 --- a/tools/testing/selftests/bpf/prog_tests/log_fixup.c +++ b/tools/testing/selftests/bpf/prog_tests/log_fixup.c @@ -124,7 +124,7 @@ static void missing_map(void) ASSERT_FALSE(bpf_map__autocreate(skel->maps.missing_map), "missing_map_autocreate"); ASSERT_HAS_SUBSTR(log_buf, - "8: \n" + ": \n" "BPF map 'missing_map' is referenced but wasn't created\n", "log_buf"); diff --git a/tools/testing/selftests/bpf/prog_tests/spin_lock.c b/tools/testing/selftests/bpf/prog_tests/spin_lock.c index d9270bd3d920..f29c08d93beb 100644 --- a/tools/testing/selftests/bpf/prog_tests/spin_lock.c +++ b/tools/testing/selftests/bpf/prog_tests/spin_lock.c @@ -1,4 +1,5 @@ // SPDX-License-Identifier: GPL-2.0 +#include #include #include @@ -19,12 +20,16 @@ static struct { "; R1_w=map_value(off=0,ks=4,vs=4,imm=0)\n2: (85) call bpf_this_cpu_ptr#154\n" "R1 type=map_value expected=percpu_ptr_" }, { "lock_id_mapval_preserve", - "8: (bf) r1 = r0 ; R0_w=map_value(id=1,off=0,ks=4,vs=8,imm=0) " - "R1_w=map_value(id=1,off=0,ks=4,vs=8,imm=0)\n9: (85) call bpf_this_cpu_ptr#154\n" + "[0-9]\\+: (bf) r1 = r0 ;" + " R0_w=map_value(id=1,off=0,ks=4,vs=8,imm=0)" + " R1_w=map_value(id=1,off=0,ks=4,vs=8,imm=0)\n" + "[0-9]\\+: (85) call bpf_this_cpu_ptr#154\n" "R1 type=map_value expected=percpu_ptr_" }, { "lock_id_innermapval_preserve", - "13: (bf) r1 = r0 ; R0=map_value(id=2,off=0,ks=4,vs=8,imm=0) " - "R1_w=map_value(id=2,off=0,ks=4,vs=8,imm=0)\n14: (85) call bpf_this_cpu_ptr#154\n" + "[0-9]\\+: (bf) r1 = r0 ;" + " R0=map_value(id=2,off=0,ks=4,vs=8,imm=0)" + " R1_w=map_value(id=2,off=0,ks=4,vs=8,imm=0)\n" + "[0-9]\\+: (85) call bpf_this_cpu_ptr#154\n" "R1 type=map_value expected=percpu_ptr_" }, { "lock_id_mismatch_kptr_kptr", "bpf_spin_unlock of different lock" }, { "lock_id_mismatch_kptr_global", "bpf_spin_unlock of different lock" }, @@ -45,6 +50,24 @@ static struct { { "lock_id_mismatch_innermapval_mapval", "bpf_spin_unlock of different lock" }, }; +static int match_regex(const char *pattern, const char *string) +{ + int err, rc; + regex_t re; + + err = regcomp(&re, pattern, REG_NOSUB); + if (err) { + char errbuf[512]; + + regerror(err, &re, errbuf, sizeof(errbuf)); + PRINT_FAIL("Can't compile regex: %s\n", errbuf); + return -1; + } + rc = regexec(&re, string, 0, NULL, 0); + regfree(&re); + return rc == 0 ? 1 : 0; +} + static void test_spin_lock_fail_prog(const char *prog_name, const char *err_msg) { LIBBPF_OPTS(bpf_object_open_opts, opts, .kernel_log_buf = log_buf, @@ -74,7 +97,11 @@ static void test_spin_lock_fail_prog(const char *prog_name, const char *err_msg) goto end; } - if (!ASSERT_OK_PTR(strstr(log_buf, err_msg), "expected error message")) { + ret = match_regex(err_msg, log_buf); + if (!ASSERT_GE(ret, 0, "match_regex")) + goto end; + + if (!ASSERT_TRUE(ret, "no match for expected error message")) { fprintf(stderr, "Expected: %s\n", err_msg); fprintf(stderr, "Verifier: %s\n", log_buf); }