Hi Eduard, Thanks for sending the report! > On Aug 29, 2024, at 5:05 PM, Eduard Zingerman <eddyz87@xxxxxxxxx> wrote: > > Hi Arnaldo, Alan, > > After recent pahole changes [1] BPF CI fails for s390 [2]. > Song Liu identified that there is a mismatch between endianness of BTF > in .BTF and .BTF.base sections. Clarification: With the regression, _both_ .BTF and .BTF.base sections (or at least part of these sections) are in little endian for s390: $ objdump -s -j .BTF bpf_testmod.ko | head bpf_testmod.ko: file format elf64-big Contents of section .BTF: 0000 9feb0100 18000000 00000000 301a0000 ............0... 0010 301a0000 80110000 00000000 0000000a 0............... 0020 24000000 00000000 00000003 00000000 $............... 0030 28000000 06000000 2b000000 00000000 (.......+....... 0040 0000000a 29000000 ea010000 03000004 ....)........... 0050 18000000 04020000 1e010000 00000000 ................ $ objdump -s -j .BTF.base bpf_testmod.ko | head bpf_testmod.ko: file format elf64-big Contents of section .BTF.base: 0000 9feb0100 18000000 00000000 fc010000 ................ 0010 fc010000 ea010000 01000000 00000001 ................ 0020 08000000 40000000 13000000 00000001 ....@........... 0030 01000000 08000000 18000000 00000001 ................ 0040 04000000 20000000 25000000 00000001 .... ...%....... 0050 01000000 08000001 31000000 00000001 ........1....... Before the regression, the "9feb" part was "eb9f" for s390: $ objdump -s -j .BTF bpf_testmod.ko | head bpf_testmod.ko: file format elf64-big Contents of section .BTF: 0000 eb9f0100 00000018 00000000 00001560 ...............` 0010 00001560 00000fc2 00000000 0a000000 ...`............ Thanks, Song