Re: [bpf-next v8 3/3] selftests/bpf: Add tests for bpf_copy_from_user_task_str

[Marcus Wichelmann <marcus.wichelmann@hetzner-cloud.de>]

Am 21.02.25 um 19:26 schrieb Andrii Nakryiko:
> On Fri, Feb 21, 2025 at 7:01 AM Marcus Wichelmann
> <marcus.wichelmann@hetzner-cloud.de> wrote:
>>
>> Hi,
>>
>> I'm not sure what I'm doing wrong, but after rebasing on latest bpf-next
>> which includes this patch, I'm no longer able to build the bpf selftests:
>>
>> # pushd tools/testing/selftests/bpf/
>> # make -j80
>> [...]
>>     GEN-SKEL [test_progs] bpf_iter_task_vmas.skel.h
>>     CLNG-BPF [test_progs] bpf_iter_tasks.bpf.o
>> progs/bpf_iter_tasks.c:98:8: error: call to undeclared function 'bpf_copy_from_user_task_str'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
>>      98 |         ret = bpf_copy_from_user_task_str((char *)task_str1, sizeof(task_str1), ptr, task, 0);
>>         |               ^
>> 1 error generated.
>> make: *** [Makefile:733: /root/linux/tools/testing/selftests/bpf/bpf_iter_tasks.bpf.o] Error 1
>>
>> I suppose the function definition should be in the vmlinux.h?
>>
> 
> Yes, it should be in vmlinux.h, and if you don't have it, then you
> must have a bit too old pahole.
> 
> $ git tag --contains ce4d0bc0200e3
> v1.27
> v1.28

Ah, my pahole version was 1.25. Compiling a newer version from source did the trick.
This was really the last thing I would have thought of.

Thank you very much for your help!

Marcus