On Mon, Apr 12, 2021 at 10:32 PM kernel test robot <lkp@intel.com> wrote:
>    m68k-linux-ld: kernel/bpf/verifier.o: in function `check_helper_call.isra.0':
> >> verifier.c:(.text+0xf79e): undefined reference to `bpf_printf_prepare'
>    m68k-linux-ld: kernel/bpf/helpers.o: in function `bpf_base_func_proto':
> >> helpers.c:(.text+0xd82): undefined reference to `bpf_snprintf_proto'

I'll move the implementation of bpf_printf_prepare/bpf_printf_cleanup
and bpf_snprintf to kernel/bpf/helpers.c so that they all get built on
kernels with CONFIG_BPF_SYSCALL but not CONFIG_BPF_EVENTS.