• Yonghong Song's avatar
    tools/bpf: add log_level to bpf_load_program_attr · a4021a35
    Yonghong Song authored
    The kernel verifier has three levels of logs:
        0: no logs
        1: logs mostly useful
      > 1: verbose
    
    Current libbpf API functions bpf_load_program_xattr() and
    bpf_load_program() cannot specify log_level.
    The bcc, however, provides an interface for user to
    specify log_level 2 for verbose output.
    
    This patch added log_level into structure
    bpf_load_program_attr, so users, including bcc, can use
    bpf_load_program_xattr() to change log_level. The
    supported log_level is 0, 1, and 2.
    
    The bpf selftest test_sock.c is modified to enable log_level = 2.
    If the "verbose" in test_sock.c is changed to true,
    the test will output logs like below:
      $ ./test_sock
      func#0 @0
      0: R1=ctx(id=0,off=0,imm=0) R10=fp0,call_-1
      0: (bf) r6 = r1
      1: R1=ctx(id=0,off=0,imm=0) R6_w=ctx(id=0,off=0,imm=0) R10=fp0,call_-1
      1: (61) r7 = *(u32 *)(r6 +28)
      invalid bpf_context access off=28 size=4
    
      Test case: bind4 load with invalid access: src_ip6 .. [PASS]
      ...
      Test case: bind6 allow all .. [PASS]
      Summary: 16 PASSED, 0 FAILED
    
    Some test_sock tests are negative tests and verbose verifier
    log will be printed out as shown in the above.
    Signed-off-by: default avatarYonghong Song <yhs@fb.com>
    Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
    a4021a35
test_sock.c 9.15 KB