From 63bb645b9da373c29ba4b5bea14e80c49e676694 Mon Sep 17 00:00:00 2001 From: Eduard Zingerman Date: Fri, 21 Apr 2023 20:42:11 +0300 Subject: [PATCH] selftests/bpf: Add notion of auxiliary programs for test_loader In order to express test cases that use bpf_tail_call() intrinsic it is necessary to have several programs to be loaded at a time. This commit adds __auxiliary annotation to the set of annotations supported by test_loader.c. Programs marked as auxiliary are always loaded but are not treated as a separate test. For example: void dummy_prog1(void); struct { __uint(type, BPF_MAP_TYPE_PROG_ARRAY); __uint(max_entries, 4); __uint(key_size, sizeof(int)); __array(values, void (void)); } prog_map SEC(".maps") = { .values = { [0] = (void *) &dummy_prog1, }, }; SEC("tc") __auxiliary __naked void dummy_prog1(void) { asm volatile ("r0 = 42; exit;"); } SEC("tc") __description("reference tracking: check reference or tail call") __success __retval(0) __naked void check_reference_or_tail_call(void) { asm volatile ( "r2 = %[prog_map] ll;" "r3 = 0;" "call %[bpf_tail_call];" "r0 = 0;" "exit;" :: __imm(bpf_tail_call), : __clobber_all); } Signed-off-by: Eduard Zingerman Link: https://lore.kernel.org/r/20230421174234.2391278-2-eddyz87@gmail.com Signed-off-by: Alexei Starovoitov --- tools/testing/selftests/bpf/progs/bpf_misc.h | 6 ++ tools/testing/selftests/bpf/test_loader.c | 89 +++++++++++++++++++++------- 2 files changed, 73 insertions(+), 22 deletions(-) diff --git a/tools/testing/selftests/bpf/progs/bpf_misc.h b/tools/testing/selftests/bpf/progs/bpf_misc.h index 3b307de..d3c1217 100644 --- a/tools/testing/selftests/bpf/progs/bpf_misc.h +++ b/tools/testing/selftests/bpf/progs/bpf_misc.h @@ -53,6 +53,10 @@ * - A numeric value. * Multiple __flag attributes could be specified, the final flags * value is derived by applying binary "or" to all specified values. + * + * __auxiliary Annotated program is not a separate test, but used as auxiliary + * for some other test cases and should always be loaded. + * __auxiliary_unpriv Same, but load program in unprivileged mode. */ #define __msg(msg) __attribute__((btf_decl_tag("comment:test_expect_msg=" msg))) #define __failure __attribute__((btf_decl_tag("comment:test_expect_failure"))) @@ -65,6 +69,8 @@ #define __flag(flag) __attribute__((btf_decl_tag("comment:test_prog_flags="#flag))) #define __retval(val) __attribute__((btf_decl_tag("comment:test_retval="#val))) #define __retval_unpriv(val) __attribute__((btf_decl_tag("comment:test_retval_unpriv="#val))) +#define __auxiliary __attribute__((btf_decl_tag("comment:test_auxiliary"))) +#define __auxiliary_unpriv __attribute__((btf_decl_tag("comment:test_auxiliary_unpriv"))) /* Convenience macro for use with 'asm volatile' blocks */ #define __naked __attribute__((naked)) diff --git a/tools/testing/selftests/bpf/test_loader.c b/tools/testing/selftests/bpf/test_loader.c index 40c9b7d..b4edd84 100644 --- a/tools/testing/selftests/bpf/test_loader.c +++ b/tools/testing/selftests/bpf/test_loader.c @@ -25,6 +25,8 @@ #define TEST_TAG_DESCRIPTION_PFX "comment:test_description=" #define TEST_TAG_RETVAL_PFX "comment:test_retval=" #define TEST_TAG_RETVAL_PFX_UNPRIV "comment:test_retval_unpriv=" +#define TEST_TAG_AUXILIARY "comment:test_auxiliary" +#define TEST_TAG_AUXILIARY_UNPRIV "comment:test_auxiliary_unpriv" /* Warning: duplicated in bpf_misc.h */ #define POINTER_VALUE 0xcafe4all @@ -59,6 +61,8 @@ struct test_spec { int log_level; int prog_flags; int mode_mask; + bool auxiliary; + bool valid; }; static int tester_init(struct test_loader *tester) @@ -87,6 +91,11 @@ static void free_test_spec(struct test_spec *spec) free(spec->unpriv.name); free(spec->priv.expect_msgs); free(spec->unpriv.expect_msgs); + + spec->priv.name = NULL; + spec->unpriv.name = NULL; + spec->priv.expect_msgs = NULL; + spec->unpriv.expect_msgs = NULL; } static int push_msg(const char *msg, struct test_subspec *subspec) @@ -204,6 +213,12 @@ static int parse_test_spec(struct test_loader *tester, spec->unpriv.expect_failure = false; spec->mode_mask |= UNPRIV; has_unpriv_result = true; + } else if (strcmp(s, TEST_TAG_AUXILIARY) == 0) { + spec->auxiliary = true; + spec->mode_mask |= PRIV; + } else if (strcmp(s, TEST_TAG_AUXILIARY_UNPRIV) == 0) { + spec->auxiliary = true; + spec->mode_mask |= UNPRIV; } else if (str_has_pfx(s, TEST_TAG_EXPECT_MSG_PFX)) { msg = s + sizeof(TEST_TAG_EXPECT_MSG_PFX) - 1; err = push_msg(msg, &spec->priv); @@ -314,6 +329,8 @@ static int parse_test_spec(struct test_loader *tester, } } + spec->valid = true; + return 0; cleanup: @@ -516,16 +533,18 @@ void run_subtest(struct test_loader *tester, struct bpf_object_open_opts *open_opts, const void *obj_bytes, size_t obj_byte_cnt, + struct test_spec *specs, struct test_spec *spec, bool unpriv) { struct test_subspec *subspec = unpriv ? &spec->unpriv : &spec->priv; + struct bpf_program *tprog, *tprog_iter; + struct test_spec *spec_iter; struct cap_state caps = {}; - struct bpf_program *tprog; struct bpf_object *tobj; struct bpf_map *map; - int retval; - int err; + int retval, err, i; + bool should_load; if (!test__start_subtest(subspec->name)) return; @@ -546,15 +565,23 @@ void run_subtest(struct test_loader *tester, if (!ASSERT_OK_PTR(tobj, "obj_open_mem")) /* shouldn't happen */ goto subtest_cleanup; - bpf_object__for_each_program(tprog, tobj) - bpf_program__set_autoload(tprog, false); + i = 0; + bpf_object__for_each_program(tprog_iter, tobj) { + spec_iter = &specs[i++]; + should_load = false; + + if (spec_iter->valid) { + if (strcmp(bpf_program__name(tprog_iter), spec->prog_name) == 0) { + tprog = tprog_iter; + should_load = true; + } - bpf_object__for_each_program(tprog, tobj) { - /* only load specified program */ - if (strcmp(bpf_program__name(tprog), spec->prog_name) == 0) { - bpf_program__set_autoload(tprog, true); - break; + if (spec_iter->auxiliary && + spec_iter->mode_mask & (unpriv ? UNPRIV : PRIV)) + should_load = true; } + + bpf_program__set_autoload(tprog_iter, should_load); } prepare_case(tester, spec, tobj, tprog); @@ -617,11 +644,12 @@ static void process_subtest(struct test_loader *tester, skel_elf_bytes_fn elf_bytes_factory) { LIBBPF_OPTS(bpf_object_open_opts, open_opts, .object_name = skel_name); + struct test_spec *specs = NULL; struct bpf_object *obj = NULL; struct bpf_program *prog; const void *obj_bytes; + int err, i, nr_progs; size_t obj_byte_cnt; - int err; if (tester_init(tester) < 0) return; /* failed to initialize tester */ @@ -631,25 +659,42 @@ static void process_subtest(struct test_loader *tester, if (!ASSERT_OK_PTR(obj, "obj_open_mem")) return; - bpf_object__for_each_program(prog, obj) { - struct test_spec spec; + nr_progs = 0; + bpf_object__for_each_program(prog, obj) + ++nr_progs; + + specs = calloc(nr_progs, sizeof(struct test_spec)); + if (!ASSERT_OK_PTR(specs, "Can't alloc specs array")) + return; - /* if we can't derive test specification, go to the next test */ - err = parse_test_spec(tester, obj, prog, &spec); - if (err) { + i = 0; + bpf_object__for_each_program(prog, obj) { + /* ignore tests for which we can't derive test specification */ + err = parse_test_spec(tester, obj, prog, &specs[i++]); + if (err) PRINT_FAIL("Can't parse test spec for program '%s'\n", bpf_program__name(prog)); + } + + i = 0; + bpf_object__for_each_program(prog, obj) { + struct test_spec *spec = &specs[i++]; + + if (!spec->valid || spec->auxiliary) continue; - } - if (spec.mode_mask & PRIV) - run_subtest(tester, &open_opts, obj_bytes, obj_byte_cnt, &spec, false); - if (spec.mode_mask & UNPRIV) - run_subtest(tester, &open_opts, obj_bytes, obj_byte_cnt, &spec, true); + if (spec->mode_mask & PRIV) + run_subtest(tester, &open_opts, obj_bytes, obj_byte_cnt, + specs, spec, false); + if (spec->mode_mask & UNPRIV) + run_subtest(tester, &open_opts, obj_bytes, obj_byte_cnt, + specs, spec, true); - free_test_spec(&spec); } + for (i = 0; i < nr_progs; ++i) + free_test_spec(&specs[i]); + free(specs); bpf_object__close(obj); } -- 2.7.4