The issue appears to be that update-initramfs creates uncompressed images. I have the same error but have been dealing with a different issue of it failing to boot with a custom kernel by UUID which is why I haven't posted a bug report. However, since this issue appears to be related, upon further inspection I find that none of the initramfs images being created are actually compressed at all.
file /boot/initrd.img* /boot/initrd.img: symbolic link to initrd.img-5.4.0-40-generic /boot/initrd.img-5.4.0-33-generic: ASCII cpio archive (SVR4 with no CRC) /boot/initrd.img-5.4.0-37-generic: ASCII cpio archive (SVR4 with no CRC) /boot/initrd.img-5.4.0-39-generic: ASCII cpio archive (SVR4 with no CRC) /boot/initrd.img-5.4.0-40-generic: ASCII cpio archive (SVR4 with no CRC) These should all be lz4 images. I tried changing the initramfs config to gzip but it still did not show a compressed file. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1835660 Title: initramfs unpacking failed To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/initramfs-tools/+bug/1835660/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
