On Fri, May 31, 2024 at 10:17:53AM +0800, Hengqi Chen wrote: > Hi Tony, > > On Fri, May 31, 2024 at 9:30 AM Tony Ambardar <tony.ambardar@xxxxxxxxx> wrote: > > > > Hello, > > > > For some time now I'm seeing multiple issues during BTF generation while > > building recent kernels targeting mips64el, and would appreciate some help > > to understand and fix the problems. > > > > Some relate to resolve_btfids: > > > > > LD vmlinux > > > BTFIDS vmlinux > > > WARN: resolve_btfids: unresolved symbol bpf_verify_pkcs7_signature > > > WARN: resolve_btfids: unresolved symbol bpf_session_cookie > > > WARN: resolve_btfids: unresolved symbol bpf_lookup_user_key > > > WARN: resolve_btfids: unresolved symbol bpf_lookup_system_key > > > WARN: resolve_btfids: unresolved symbol bpf_key_put > > > WARN: resolve_btfids: unresolved symbol bpf_iter_task_next > > > WARN: resolve_btfids: unresolved symbol bpf_iter_css_task_new > > > WARN: resolve_btfids: unresolved symbol bpf_get_file_xattr > > > WARN: resolve_btfids: unresolved symbol bpf_ct_insert_entry > > > WARN: resolve_btfids: unresolved symbol bpf_cgroup_release > > > WARN: resolve_btfids: unresolved symbol bpf_cgroup_from_id > > > WARN: resolve_btfids: unresolved symbol bpf_cgroup_acquire > > > WARN: resolve_btfids: unresolved symbol bpf_arena_free_pages > > > NM System.map > > > SORTTAB vmlinux > > > OBJCOPY vmlinux.32 > > > > These do not appear to be #ifdef-related and have similar past reports [1]. I can reproduce the warning just for bpf_session_cookie, which has fix in progress: https://lore.kernel.org/bpf/20240531071557.MvfIqkn7@xxxxxxxxxxxxx/T/#t > > > > I also see many pahole failures during BTF encoding of modules, such as: > > > > > CC [M] net/ipv6/netfilter/nft_fib_ipv6.mod.o > > > CC [M] net/ipv6/netfilter/ip6t_REJECT.mod.o > > > CC [M] net/psample/psample.mod.o > > > LD [M] crypto/cmac.ko > > > BTF [M] crypto/cmac.ko > > > die__process: DW_TAG_compile_unit, DW_TAG_type_unit, DW_TAG_partial_unit > > > or DW_TAG_skeleton_unit expected got member (0xd)! > > The issue seems to be related to elfutils. Have you tried build from > the latest elfutils source ? > I saw the latest MIPS backend in elfutils already implemented the > reloc_simple_type hook. hi, +1, could you also check the pahole version you used? jirka > > > > LD [M] lib/test_bpf.ko > > > BTF [M] lib/test_bpf.ko > > > die__process: DW_TAG_compile_unit, DW_TAG_type_unit, DW_TAG_partial_unit > > > or DW_TAG_skeleton_unit expected got member (0xd)! > > > LD [M] lib/crc-ccitt.ko > > > BTF [M] lib/crc-ccitt.ko > > > die__process_unit: DW_TAG_compile_unit (0x11) @ <0x9331> not handled! > > > die__process_unit: tag not supported 0x11 (compile_unit)! > > > die__process: got compile_unit unexpected tag after DW_TAG_compile_unit! > > > LD [M] lib/libcrc32c.ko > > > BTF [M] lib/libcrc32c.ko > > > die__process_unit: DW_TAG_compile_unit (0x11) @ <0x99a5> not handled! > > > die__process_unit: tag not supported 0x11 (compile_unit)! > > > die__process: got compile_unit unexpected tag after DW_TAG_compile_unit! > > > LD [M] lib/ts_kmp.ko > > > BTF [M] lib/ts_kmp.ko > > > LD [M] lib/ts_bm.ko > > > BTF [M] lib/ts_bm.ko > > > die__process: DW_TAG_compile_unit, DW_TAG_type_unit, DW_TAG_partial_unit > > > or DW_TAG_skeleton_unit expected got member (0xd)! > > > die__process: DW_TAG_compile_unit, DW_TAG_type_unit, DW_TAG_partial_unit > > > or DW_TAG_skeleton_unit expected got member (0xd)! > > > > I have seen reports of various similar "die__" messages on the dwarves > > list and repo, with the hint of an elfutils connection [2] but nothing > > conclusive. > > > > Details of the git commit and build environment are as follows: > > > > > $ git log -1 --oneline bpf/master > > > 9dfdb706e164 (bpf/master) selftests/bpf: fix inet_csk_accept prototype in > > > test_sk_storage_tracing.c > > > > > > $ lsb_release -a > > > Description: Ubuntu 22.04.4 LTS > > > > > > $ cat gcc-compile.txt > > > ARCH=mips CROSS_COMPILE=mips64el-linux-gnuabi64- CC="ccache ${CROSS_COMPILE}gcc" make -j6 > > > > > > $ mips64el-linux-gnuabi64-gcc --version > > > mips64el-linux-gnuabi64-gcc (Ubuntu 10.3.0-1ubuntu1) 10.3.0 > > > > > > $ mips64el-linux-gnuabi64-ld --version > > > GNU ld (GNU Binutils for Ubuntu) 2.38 > > > > > > $ pahole --version > > > v1.26 > > > > > > $ ldd $(which pahole) > > > linux-vdso.so.1 (0x00007fff16f3f000) > > > libdw.so.1 => /lib/x86_64-linux-gnu/libdw.so.1 (0x00007fc39d42e000) > > > libelf.so.1 => /lib/x86_64-linux-gnu/libelf.so.1 (0x00007fc39d410000) > > > libz.so.1 => /lib/x86_64-linux-gnu/libz.so.1 (0x00007fc39d3f4000) > > > libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007fc39d1cb000) > > > liblzma.so.5 => /lib/x86_64-linux-gnu/liblzma.so.5 (0x00007fc39d1a0000) > > > libbz2.so.1.0 => /lib/x86_64-linux-gnu/libbz2.so.1.0 (0x00007fc39d18d000) > > > /lib64/ld-linux-x86-64.so.2 (0x00007fc39d59d000) > > > > > > $ dpkg -s elfutils > > > Package: elfutils > > > ... > > > Version: 0.186-1build1 > > > Depends: libasm1 (>= 0.132), libc6 (>= 2.34), libdw1 (= 0.186-1build1), > > > libelf1 (= 0.186-1build1), libstdc++6 (>= 4.1.1) > > > > For reference, I also attached the full .config and build log from the > > above. > > > > I should add this is not only a problem with the latest bpf/master but > > also appears to affect the 6.6.x LTS kernel, which I tested while building > > a mips64el OpenWrt distro image. That build environment employs the latest > > gcc 13.3, binutils 2.42, pahole 1.26, and elfutils 0.191. > > > > Not only do I see similar warnings from resolve_btfids and pahole, but > > while running the distro image I encounter module loading failures that > > suggest ELF corruption in some module .ko files, based on the following: > > > > > root@OpenWrt:/# strace insmod /lib/modules/6.6.30/nf_conntrack.ko > > > ... > > > init_module(0xfff3e36160, 307448, "") = -1 EINVAL (Invalid argument) > > > ... > > > > > $ man init_module > > > ... > > > The following errors may additionally occur for init_module(): > > > ... > > > EINVAL param_values is invalid, or some part of the ELF image in > > > module_image contains inconsistencies. > > > ... > > > > I'd be grateful if some of the BTF/pahole experts could please review this > > issue and share next steps or other details I might provide. > > > > Thanks, > > Tony Ambardar > > > > Link: https://lore.kernel.org/all/202401211357.OCX9yllM-lkp@xxxxxxxxx/ [1] > > Link: https://github.com/acmel/dwarves/issues/45 [2] > > Cheers, > Hengqi >
