Error when booting: Diskfilter writes not supported

[whateverthing]

I got a ways through it, but it failed at the mkfs command:

Code:

linux  ~  sudo partprobe /dev/sda
linux  ~  sudo mkfs.ext4 -t ext4 -m 2 -L root /dev/sda1
mke2fs 1.44.1 (24-Mar-2018)
/dev/sda1 contains a LVM2_member file system
Proceed anyway? (y,N) y
/dev/sda1 is apparently in use by the system; will not make a filesystem here!
linux  ~ 