1. Unlocked bootloader is required!
2. Download the TWRP recovery
3. Boot into fastboot and type : fastboot flash recovery_ramdisk TWRP_3.2.1-0_OREO.img
4. Type: fastboot reboot
Great! Now I see the problem.
So, I want to help you learn how to solve the issue yourself.
Search that file for the words "error:" and "failed:" with the colon. Lines that start with that phrase are your problem. So, what do you see?
I'm trying to build LOS15.1 for unsupported device and I get this error https://hastebin.com/keholovona.sql
Yes, it is. Do you have a more specific scenario in mind? :D
thanks for answering. I ask if you do not have to change the kernel source code. Because the kernel is android 8.0 and LOS15 is android 8.1