On Mon, Jul 20, 2020 at 01:41:52PM -0700, Alexei Starovoitov wrote: > On Mon, Jul 20, 2020 at 10:09:43AM +0200, Christoph Hellwig wrote: > > Hi BPF and selftest maintainers. I get a very strange failure > > when trying to build the bpf selftests on current net-next master: > > > > hch@brick:~/work/linux/tools/testing/selftests/bpf$ make > > GEN vmlinux.h > > Error: failed to load BTF from /home/hch/work/linux/vmlinux: No such file or directory > > That's bpftool complaining that BTF is not present in vmlinux. > You need CONFIG_DEBUG_INFO_BTF=y and pahole >= v1.16 > You also need llvm 10 to build bpf progs. That's not a very useful error message then. Can you fix it to tell people what is wrong?