Subject: [next-20220721] Build failure powerpc (tools/bpf)

From: Sachin Sant <[email-masked]>
Date: Fri, 22 Jul 2022 12:34:14 +0530

next-20220721 build fails on IBM Power server with following error:

libbpf.c: In function 'bpf_program__attach_ksyscall':
libbpf.c:10130:45: error: '%s' directive argument is null [-Werror=format-truncation=]
   snprintf(func_name, sizeof(func_name), "__%s_sys_%s",
                                             ^~
cc1: all warnings being treated as errors
make[4]: *** [/home/linux-next/tools/build/Makefile.build:96: /home/linux-next/tools/bpf/resolve_btfids/libbpf/staticobjs/libbpf.o] Error 1
make[3]: *** [Makefile:157: /home/linux-next/tools/bpf/resolve_btfids/libbpf/staticobjs/libbpf-in.o] Error 2
make[2]: *** [Makefile:55: /home/linux-next/tools/bpf/resolve_btfids//libbpf/libbpf.a] Error 2
make[1]: *** [Makefile:76: bpf/resolve_btfids] Error 2
make: *** [Makefile:1439: tools/bpf/resolve_btfids] Error 2

next-20220719 was good. Git bisect points to following commit

Commit 708ac5bea0ce
    libbpf: add ksyscall/kretsyscall sections support for syscall kprobes

Reverting this commit allows me to build the kernel.

Have attached .config used for build.

- Sachin