linux.git/tools/testing/selftests/bpf/test_loader.c, branch v6.9

selftests/bpf: Add unit tests for bpf_arena_alloc/free_pages

2024-03-11T22:43:43+00:00

Add unit tests for bpf_arena_alloc/free_pages() functionality
and bpf_arena_common.h with a set of common helpers and macros that
is used in this test and the following patches.

Also modify test_loader that didn't support running bpf_prog_type_syscall
programs.

Signed-off-by: Alexei Starovoitov 
Signed-off-by: Andrii Nakryiko 
Link: https://lore.kernel.org/bpf/20240308010812.89848-13-alexei.starovoitov@gmail.com

selftests/bpf: detect testing prog flags support

2024-01-23T22:40:22+00:00

Various tests specify extra testing prog_flags when loading BPF
programs, like BPF_F_TEST_RND_HI32, and more recently also
BPF_F_TEST_REG_INVARIANTS. While BPF_F_TEST_RND_HI32 is old enough to
not cause much problem on older kernels, BPF_F_TEST_REG_INVARIANTS is
very fresh and unconditionally specifying it causes selftests to fail on
even slightly outdated kernels.

This breaks libbpf CI test against 4.9 and 5.15 kernels, it can break
some local development (done outside of VM), etc.

To prevent this, and guard against similar problems in the future, do
runtime detection of supported "testing flags", and only provide those
that host kernel recognizes.

Acked-by: Song Liu 
Acked-by: Jiri Olsa 
Signed-off-by: Andrii Nakryiko 
Link: https://lore.kernel.org/r/20240109231738.575844-1-andrii@kernel.org
Signed-off-by: Alexei Starovoitov

selftests/bpf: fix test_loader check message

2024-01-23T22:40:21+00:00

Seeing:

  process_subtest:PASS:Can't alloc specs array 0 nsec

... in verbose successful test log is very confusing. Use smaller
identifier-like test tag to denote that we are asserting specs array
allocation success.

Now it's much less distracting:

  process_subtest:PASS:specs_alloc 0 nsec

Signed-off-by: Andrii Nakryiko 
Acked-by: Eduard Zingerman 
Link: https://lore.kernel.org/r/20240105000909.2818934-2-andrii@kernel.org
Signed-off-by: Alexei Starovoitov

selftests/bpf: Double the size of test_loader log

2024-01-04T22:35:35+00:00

Testing long jumps requires having >32k instructions. That many
instructions require the verifier log buffer of 2 megabytes.

The regular test_progs run doesn't need an increased buffer, since
gotol test with 40k instructions doesn't request a log,
but test_progs -v will set the verifier log level.
Hence to avoid breaking gotol test with -v increase the buffer size.

Signed-off-by: Ilya Leoshkevich 
Acked-by: Yonghong Song 
Acked-by: John Fastabend 
Link: https://lore.kernel.org/r/20240102193531.3169422-3-iii@linux.ibm.com
Signed-off-by: Alexei Starovoitov

bpf: selftests: test_loader: Support __btf_path() annotation

2023-12-13T23:42:19+00:00

This commit adds support for per-prog btf_custom_path. This is necessary
for testing CO-RE relocations on non-vmlinux types using test_loader
infrastructure.

Acked-by: Andrii Nakryiko 
Signed-off-by: Daniel Xu 
Link: https://lore.kernel.org/r/660ea7f2fdbdd5103bc1af87c9fc931f05327926.1702325874.git.dxu@dxuuu.xyz
Signed-off-by: Martin KaFai Lau

bpf: rename BPF_F_TEST_SANITY_STRICT to BPF_F_TEST_REG_INVARIANTS

2023-11-17T18:30:02+00:00

Rename verifier internal flag BPF_F_TEST_SANITY_STRICT to more neutral
BPF_F_TEST_REG_INVARIANTS. This is a follow up to [0].

A few selftests and veristat need to be adjusted in the same patch as
well.

  [0] https://patchwork.kernel.org/project/netdevbpf/patch/20231112010609.848406-5-andrii@kernel.org/

Signed-off-by: Andrii Nakryiko 
Link: https://lore.kernel.org/r/20231117171404.225508-1-andrii@kernel.org
Signed-off-by: Alexei Starovoitov

selftests/bpf: set BPF_F_TEST_SANITY_SCRIPT by default

2023-11-15T20:03:42+00:00

Make sure to set BPF_F_TEST_SANITY_STRICT program flag by default across
most verifier tests (and a bunch of others that set custom prog flags).

There are currently two tests that do fail validation, if enforced
strictly: verifier_bounds/crossing_64_bit_signed_boundary_2 and
verifier_bounds/crossing_32_bit_signed_boundary_2. To accommodate them,
we teach test_loader a flag negation:

__flag(!) will *clear* specified flag, allowing easy opt-out.

We apply __flag(!BPF_F_TEST_SANITY_STRICT) to these to tests.

Also sprinkle BPF_F_TEST_SANITY_STRICT everywhere where we already set
test-only BPF_F_TEST_RND_HI32 flag, for completeness.

Acked-by: Eduard Zingerman 
Signed-off-by: Andrii Nakryiko 
Link: https://lore.kernel.org/r/20231112010609.848406-12-andrii@kernel.org
Signed-off-by: Alexei Starovoitov

selftests/bpf: Fix compiler warnings reported in -O2 mode

2023-10-06T18:17:28+00:00

Fix a bunch of potentially unitialized variable usage warnings that are
reported by GCC in -O2 mode. Also silence overzealous stringop-truncation
class of warnings.

Signed-off-by: Andrii Nakryiko 
Signed-off-by: Daniel Borkmann 
Acked-by: Jiri Olsa 
Link: https://lore.kernel.org/bpf/20231006175744.3136675-1-andrii@kernel.org

selftests/bpf: Add notion of auxiliary programs for test_loader

2023-04-21T19:16:56+00:00

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

selftests/bpf: add pre bpf_prog_test_run_opts() callback for test_loader

2023-04-20T23:49:16+00:00

When a test case is annotated with __retval tag the test_loader engine
would use libbpf's bpf_prog_test_run_opts() to do a test run of the
program and compare retvals.

This commit allows to perform arbitrary actions on bpf object right
before test loader invokes bpf_prog_test_run_opts(). This could be
used to setup some state for program execution, e.g. fill some maps.

Signed-off-by: Eduard Zingerman 
Link: https://lore.kernel.org/r/20230420232317.2181776-4-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov