From: Jeremy Linton on gitlab.com https://gitlab.com/cki-project/kernel-ark/-/merge_requests/3460#note_2237233...
Well, that's going to be a problem I should have forseen given I hacked some of the kexec/zboot stuff a year back.
So, yes, this should probably be on hold until kexec can decompress these because checking the code right now it can only do lzma/gzip AFAIK.