Hi!
I'm trying to build kernel 5.9.1 for arm64, and my dotconfig has
`CONFIG_DEBUG_INFO_BTF=y`, which requires pahole for building. However, pahole
version 1.18 segfaults during the build, as can be seen below:
PAHOLE: Error: Found symbol of zero size when encoding btf (sym:
'__kvm_nvhe_arm64_ssbd_callback_required', cu:
'arch/arm64/kernel/cpu_errata.c').
PAHOLE: Error: Use '-j' or '--force' to ignore such symbols and force
emit the btf.
scripts/link-vmlinux.sh: line 141: 43837 Segmentation fault
LLVM_OBJCOPY=${OBJCOPY} ${PAHOLE} -J ${1}
LD .tmp_vmlinux.kallsyms1
KSYM .tmp_vmlinux.kallsyms1.o
LD .tmp_vmlinux.kallsyms2
KSYM .tmp_vmlinux.kallsyms2.o
LD vmlinux
BTFIDS vmlinux
FAILED: load BTF from vmlinux: Unknown error -2make: ***
[Makefile:1162: vmlinux] Error 255
It is possible to force the build to continue if
LLVM_OBJCOPY=${OBJCOPY} ${PAHOLE} -J ${1}
in scripts/link-vmlinux.sh is changed to
LLVM_OBJCOPY=${OBJCOPY} ${PAHOLE} -J --btf_encode_force ${1}
The suggested `-j` or `--force` flags don't exist, since they were removed in
[1]. I believe `--btf_encode_force` should be suggested instead.
It should be noted that the same build, but with pahole version 1.17, works
without issue, so I think this is either a regression in pahole or the script
will need to be changed for newer versions of pahole.
- [1] https://git.kernel.org/pub/scm/devel/pahole/pahole.git/commit/pahole.c?h=v1.18&id=1abc001417b579b86a9b27ff88c9095d8f498a46
Thanks,
Érico
