Arch Linux

HotDogEnemy

Member

Registered: 2020-11-24

Posts: 72

[SOLVED] Compiling older kernel fails with error

I'm currently trying to compile an older kernel (between the 5.15 and 5.16 kernels from torvalds git repo), but it keeps failing after I run make -j4. I followed the configuration steps from the wiki - copying the configuration of the currently running Linux kernel, after which I used modprobed-db to disable unneeded modules in the config. But since GCC-12 would not work due to some changes with the way it handles errors, I had to download the gcc11 package and modify the makefile to use gcc-11 and g++-11 instead. Then I ran make -j4 which results in an error about BTF.

The error message that shows when running make -j4 is as follows:

$ make -j4
  DESCEND objtool
  DESCEND bpf/resolve_btfids
  CALL    scripts/atomic/check-atomics.sh
  CALL    scripts/checksyscalls.sh
  CHK     include/generated/compile.h
  GEN     .version
  CHK     include/generated/compile.h
  UPD     include/generated/compile.h
  CC      init/version.o
  AR      init/built-in.a
  LD      vmlinux.o
  MODPOST vmlinux.symvers
  MODINFO modules.builtin.modinfo
  GEN     modules.builtin
  LD      .tmp_vmlinux.btf
ld: warning: .tmp_vmlinux.btf has a LOAD segment with RWX permissions
  BTF     .btf.vmlinux.bin.o
  LD      .tmp_vmlinux.kallsyms1
ld: warning: .tmp_vmlinux.kallsyms1 has a LOAD segment with RWX permissions
  KSYMS   .tmp_vmlinux.kallsyms1.S
  AS      .tmp_vmlinux.kallsyms1.S
  LD      .tmp_vmlinux.kallsyms2
ld: warning: .tmp_vmlinux.kallsyms2 has a LOAD segment with RWX permissions
  KSYMS   .tmp_vmlinux.kallsyms2.S
  AS      .tmp_vmlinux.kallsyms2.S
  LD      vmlinux
ld: warning: vmlinux has a LOAD segment with RWX permissions
  BTFIDS  vmlinux
FAILED: load BTF from vmlinux: Invalid argument
make: *** [Makefile:1187: vmlinux] Error 255
make: *** Deleting file 'vmlinux'

However, compiling a newer kernel (v6.1-rc4) works just fine, and the bzImage is generated successfully.

I searched around online, however I haven't found any solutions yet. Any help would be appreciated!

Last edited by HotDogEnemy (2022-11-12 08:02:20)

xerxes_

Member

Registered: 2018-04-29

Posts: 919

Re: [SOLVED] Compiling older kernel fails with error

Check permissions of your files; maybe they should not be executable?

Scimmia

Fellow

Registered: 2012-09-01

Posts: 12,762

Re: [SOLVED] Compiling older kernel fails with error

You may need an older pahole to build.

HotDogEnemy

Member

Registered: 2020-11-24

Posts: 72

Re: [SOLVED] Compiling older kernel fails with error

Check permissions of your files; maybe they should not be executable?

I checked, but everything seems fine.

You may need an older pahole to build.

I actually figured it out, seems like the tags in the torvalds kernel branch don't get updated after its released, so I was missing some fixes. All I had to do was download a recent 5.15 kernel (5.15.77 from stable branch in this case) and replace the file scripts/pahole-flags.sh of the older kernel (the kernel I was trying to build) with the scripts/pahole-flags.sh of the newer kernel (the 5.15.77 kernel).

After doing this, the kernel compiled and booted up successfully.

Marking as solved, thank you to everyone who took the time to reply!