On Tue, Jul 12, 2022 at 2:12 AM Jiri Olsa <olsajiri@xxxxxxxxx> wrote: > > On Mon, Jul 11, 2022 at 02:53:58PM -0700, Donald Chan wrote: > > On Mon, Jul 11, 2022 at 1:34 AM Jiri Olsa <olsajiri@xxxxxxxxx> wrote: > > > > > > On Mon, Jul 11, 2022 at 09:19:45AM +0200, Jiri Olsa wrote: > > > > On Sun, Jul 10, 2022 at 10:57:01PM -0700, Donald Chan wrote: > > > > > Hi, > > > > > > > > > > I am trying to enable CONFIG_DEBUG_INFO_BTF when building a > > > > > Yocto-based Linux kernel....but it is failing with this error: > > > > > > > > > > | LD .tmp_vmlinux.btf > > > > > | BTF .btf.vmlinux.bin.o > > > > > | LD .tmp_vmlinux.kallsyms1 > > > > > | KSYMS .tmp_vmlinux.kallsyms1.S > > > > > | AS .tmp_vmlinux.kallsyms1.S > > > > > | LD .tmp_vmlinux.kallsyms2 > > > > > | KSYMS .tmp_vmlinux.kallsyms2.S > > > > > | AS .tmp_vmlinux.kallsyms2.S > > > > > | LD vmlinux > > > > > | BTFIDS vmlinux > > > > > | FAILED: load BTF from vmlinux: No such file or directory > > > > > > > > > > I dug deeper and it seems that the resolve_btfids utility is not able > > > > > to find any relevant .BTF section (at btf__parse from function > > > > > symbols_resolve). > > > > > > > > > > Dumped the vmlinux and also confirmed there is only .BTF_ids section: > > > > > > > > > > [2993] .rela___ksymtab_g RELA 0000000000000000 17174de0 > > > > > 0000000000000048 0000000000000018 I 22807 2992 8 > > > > > [2994] .BTF_ids PROGBITS 0000000000000000 0105c504 > > > > > 00000000000000fc 0000000000000000 A 0 0 1 > > > > > > > > > > What could be wrong? Sample config is available at > > > > > https://gist.github.com/hoiho-amzn/964eb0cf2b4459f6775d7af1da7b4056 > > > > > > I compiled x86_64 bpf-next/master kernel with your config with no problems, > > > could you share more details? like: > > > - version of dwarves/pahole > > > > $ pahole --version > > v1.22 > > > > > - clang/gcc? versions > > > - V=1 compile log > > > - command line options > > > > I will need some more time to gather the logs. Hopefully the pahole > > and kernel branch will give some initial clue. > > > > > - tree/branch you're on > > > > This is from Yocto and they use 5.15 - > > https://git.yoctoproject.org/linux-yocto/tree/?h=v5.15/standard/base&id=ebfb1822e9f9726d8c587fc0f60cfed43fa0873e > > could you test that on either bpf/master or bpf-next/master tree? > > jirka Finally figured out the mystery - I was building on Ubuntu 18.04, and libelf/elfutils was too old (0.170). After upgrading to Ubuntu 22.04, I was able to build. Many thanks! > > > > > > - anything else ;-) > > > > > > thanks, > > > jirka > > > > > > > > > > > > > The issue exists on x86_64, I also have tried armv7 with the same > > > > > result so doesn't seem to be arch-specific. > > > > > > > > hi, > > > > do you use any special command line options? > > > > what tree/branch are you on? > > > > > > > > thanks, > > > > jirka > > > > > > > > > > > > > > Thanks > > > > > Donald
