ENCRYPTED KEYS

modulename: ecryptfs_format.ko

configname: CONFIG_ENCRYPTED_KEYS

Linux Kernel Configuration
└─>Security options
└─>ENCRYPTED KEYS
In linux kernel since version 2.6.38 (release Date: 2011-03-14)  
This option provides support for create/encrypting/decrypting keys
in the kernel. Encrypted keys are kernel generated random numbers,
which are encrypted/decrypted with a 'master' symmetric key. The
'master' key can be either a trusted-key or user-key type.
Userspace only ever sees/stores encrypted blobs.

If you are unsure as to whether this is required, answer N.

source code: