.`fips-mode-setup` checks for use of Argon2 KDF in open LUKS volumes before enabling FIPS mode The `fips-mode-setup` system management command now detects key derivation functions (KDF) used in currently open LUKS volumes, and aborts if it detects usage of Argon2 KDF. This is because Argon2 KDF is not FIPS-compatible, so preventing its use helps ensure FIPS compliance. As a result, switching into FIPS mode on a system with open LUKS volumes that use Argon2 as a KDF is blocked until those volumes are closed or converted to a different KDF.