On Mon, Sep 14, 2020 at 03:26:33PM -0700, Andrii Nakryiko wrote: > On Mon, Sep 14, 2020 at 11:25 AM Jiri Olsa <jolsa@xxxxxxxxxx> wrote: > > > > On Mon, Sep 14, 2020 at 10:48:36AM -0400, Veronika Kabatova wrote: > > > > > > Hello, > > > > > > we tested the bpf-next tree with CKI and ran across build failures. The > > > important part of the build log is: > > > > > > 00:18:05 GEN .version > > > 00:18:05 CHK include/generated/compile.h > > > 00:18:05 LD vmlinux.o > > > 00:18:27 MODPOST vmlinux.symvers > > > 00:18:27 MODINFO modules.builtin.modinfo > > > 00:18:27 GEN modules.builtin > > > 00:18:27 LD .tmp_vmlinux.btf > > > 00:18:42 BTF .btf.vmlinux.bin.o > > > 00:19:13 LD .tmp_vmlinux.kallsyms1 > > > 00:19:19 KSYM .tmp_vmlinux.kallsyms1.o > > > 00:19:22 LD .tmp_vmlinux.kallsyms2 > > > 00:19:25 KSYM .tmp_vmlinux.kallsyms2.o > > > 00:19:28 LD vmlinux > > > 00:19:40 BTFIDS vmlinux > > > 00:19:40 FAILED unresolved symbol vfs_getattr > > > 00:19:40 make[2]: *** [Makefile:1167: vmlinux] Error 255 > > > 00:19:40 make[1]: *** [scripts/Makefile.package:109: targz-pkg] Error 2 > > > 00:19:40 make: *** [Makefile:1528: targz-pkg] Error 2 > > > > hi, > > it looks like broken BTF data to me, I checked that build > > and found we have multiple records for functions, like > > for filp_close: > > > > [23381] FUNC_PROTO '(anon)' ret_type_id=19 vlen=2 > > '(anon)' type_id=464 > > 'id' type_id=960 > > [23382] FUNC 'filp_close' type_id=23381 linkage=static > > > > > > [33073] FUNC_PROTO '(anon)' ret_type_id=19 vlen=2 > > 'filp' type_id=464 > > 'id' type_id=960 > > [33074] FUNC 'filp_close' type_id=33073 linkage=static > > > > > > or vfs_getattr: > > > > [33513] FUNC_PROTO '(anon)' ret_type_id=19 vlen=4 > > 'path' type_id=741 > > 'stat' type_id=1095 > > 'request_mask' type_id=29 > > 'query_flags' type_id=8 > > > > [33514] FUNC 'vfs_getattr' type_id=33513 linkage=static > > > > [1094] FUNC_PROTO '(anon)' ret_type_id=19 vlen=4 > > '(anon)' type_id=741 > > '(anon)' type_id=1095 > > '(anon)' type_id=29 > > '(anon)' type_id=8 > > > > [35099] FUNC 'vfs_getattr' type_id=1094 linkage=static > > > > > > and because we go through all BTF data until we resolve all we have, > > the doubled funcs will screw our internal counter and we skip a function > > > > the change below will workaround that, but I think we should fail in > > this case.. if I'm not missing something 2 FUNC records for one function > > in BTF data > > > > $ pahole --version > > v1.17 > > > > HEAD is 2bab48c5b Merge branch 'improve-bpf-tcp-cc-init' > > > > thoughts? thanks > > Can't repro this locally. It must be some bad compiler + DWARF + > pahole interaction. Can you try building pahole from latest sources > and try again? Also, what compiler did you use? What Kconfig? sorry I cut the original message, there's following container that reproduces the issue: The failure is easily reproduced with our container image that already has all the needed dependencies installed: registry.gitlab.com/cki-project/containers/builder-rawhide:latest Steps to reproduce after starting the image: git clone https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git --depth 1 curl https://gitlab.com/-/snippets/2014934/raw -o bpf-next/.config cd bpf-next/ make -j 10 INSTALL_MOD_STRIP=1 targz-pkg [root@30a9be783e4e /]# gcc --version gcc (GCC) 10.2.1 20200826 (Red Hat 10.2.1-3) I built the latest pahole in that container and still see the issue, I also tried with v1.16 version and it's still there I don't see the issue when I build kernel with another .config so I'll try to check on that now jirka
