CONFIG_XEN_FRONT_PGDIR_SHBUF (not configurable)

modulename: xen-front-pgdir-shbuf.ko

configname: CONFIG_XEN_FRONT_PGDIR_SHBUF

Linux Kernel Configuration
└─>Device Drivers
└─>Xen driver support
└─>XEN_FRONT_PGDIR_SHBUF
In linux kernel since version 5 (release Date: 2019-03-03)  
source code:
drivers/xen/xen-front-pgdir-shbuf.c
depends
CONFIG_XEN