Kerberos/SPNEGO advanced session setup

configname: CONFIG_CIFS_UPCALL

Linux Kernel Configuration
└─>File systems
└─>Network File Systems
└─>Kerberos/SPNEGO advanced session setup
In linux kernel since version 2.6.20 (release Date: 2007-02-04)  
Enables an upcall mechanism for CIFS which accesses userspace helper
utilities to provide SPNEGO packaged (RFC 4178) Kerberos tickets
which are needed to mount to certain secure servers (for which more
secure Kerberos authentication is required). If unsure, say N.