decompress-lz4-kernels

A Debian/Ubuntu kernel postinst hook which decompresses LZ4-compressed kernels.

Ubuntu started compressing their kernels with LZ4 as of the 19.10 release, and not all software yet supports that.

Who needs this

If you've ordered a new VM from BitFolk or installed one yourself from BitFolk's Xen Shell then this hook will be installed automatically and you don't need to be reading any of this.

This repository exists for people who are upgrading from an earlier version of Ubuntu and need the hook to have a bootable kernel, or just in case it helps anyone else.

Prerequisites

• extract-vmlinux. Put it in /usr/local/sbin/ and make sure it is executable
• lz4 binary from the lz4 package
• readelf binary from the binutils package

Installation

Place the decompress-lz4-kernels file in the /etc/kernel/postinst.d/ directory and make sure it is executable.

It will be called next time you install a kernel. If you'd like it to be run on a kernel you already have installed then you can force a reinstall of the package like this:

$ sudo apt reinstall linux-image-5.4.0-29-generic

Support

If you are stuck then please contact the BitFolk Users mailing list.