Could not find kallsyms_names

[dohbi]

find_kallsyms_num_syms() loops forever with boot.img in this Pixel factory image.

~/bin/vmlinux-to-elf/kallsyms-finder ./boot.img
[+] Kernel successfully decompressed in-memory (the offsets that follow will be given relative to the decompressed binary)
[+] Kernel successfully decompressed in-memory (the offsets that follow will be given relative to the decompressed binary)
[+] Version string: Linux version 4.14.170-g5513138224ab-ab6570431 (android-build@abfarm-east4-052) (Android (5484270 based on r353983c) clang version 9.0.3 (https://android.googlesource.com/toolchain/clang 745b335211bb9eadfa6aa6301f84715cee4b37c5) (https://android.googlesource.com/toolchain/llvm 60cf23e54e46c807513f7a36d0a7b777920b5881) (based on LLVM 9.0.3svn)) #1 SMP PREEMPT Tue Jun 9 02:18:01 UTC 2020
[+] Guessed architecture: aarch64 successfully in 4.52 seconds
[+] Found relocations table at file offset 0x2577ec0 (count=154559)
[+] Found kernel text candidate: 0xffffff8008300000
[+] Successfully applied 154559 relocations.
[+] Found kallsyms_token_table at file offset 0x0210c000
[+] Found kallsyms_token_index at file offset 0x0210c400
[+] Found kallsyms_markers at file offset 0x0210ab00

needle is -1 even after executing loop for 5M times.
Where should I start to debug for this?