Re: [PATCH bpf-next v9 9/9] selftests/bpf: Add tests to verify map create failure log

From: Leon Hwang

Date: Wed Feb 04 2026 - 22:55:18 EST




On 5/2/26 04:14, Alexei Starovoitov wrote:
> On Mon, Feb 2, 2026 at 6:43 AM Leon Hwang <leon.hwang@xxxxxxxxx> wrote:
>>
>> +
>> +#define BPF_LOG_FIXED 8
>> +
>> +static void test_map_create(enum bpf_map_type map_type, const char *map_name,
>> + struct bpf_map_create_opts *opts, const char *exp_msg)
>> +{
>> + const int key_size = 4, value_size = 4, max_entries = 1;
>> + char log_buf[128];
>> + int fd;
>> + LIBBPF_OPTS(bpf_log_opts, log_opts);
>> +
>> + log_buf[0] = '\0';
>> + log_opts.log_buf = log_buf;
>> + log_opts.log_size = sizeof(log_buf);
>> + log_opts.log_level = BPF_LOG_FIXED;
>
> Why? Which part of the test needs the log with this flag?

BPF_LOG_FIXED looks odd here.

This test sets 'log_level = BPF_LOG_FIXED' to match the behavior of
bpf_vlog_init() as initialized by bpf_log_attr_create_vlog() in
patch #7. BPF_LOG_FIXED is intended to be the default log_level
there.

Thanks,
Leon