CONFIG_NET_9P=y
CONFIG_NET_9P_FD=y
# CONFIG_NET_9P_VIRTIO is not set
# CONFIG_NET_9P_DEBUG is not set
CONFIG_9P_FS=y
CONFIG_9P_FSCACHE=y
CONFIG_9P_FS_POSIX_ACL=y
CONFIG_9P_FS_SECURITY=y
Let us know if you have any other trouble getting ZeroFS running