Ext4 metadata checksums: current feature status

Solution 1:

A certain Theodore Ts'o has, back in in 2015, enabled both feature by default for filesystems created with version e2fsprogs 1.43. Before that, it was only enabled when needed.

Mke2fs will now create file systems with the metadata_csum and 64bit features enabled by default. e2fsprogs/doc/RelNotes/v1.43.0.txt

That default having found its way into Ubuntu 18.04 (that is the LTS release before the current one) should mean that at least in any setup supported and used with Ubuntu, it is widely tested with kernel versions starting with 4.15. If there were serious issues left, we would know by now.

Solution 2:

metadata_csum should be stable, as it has found its way in RHEL8

64bit is the same; from ext4 man page:

This feature is set automatically, as needed