to configure a kernel for building, I create a terminal session (for my userid), then use "su" to switch to root, then run "make xconfig". This has been resulting in a "GLib-GIO:ERROR:gdbusconnection.c:2279:initable_init: assertion failed: (connection->initialization_error == NULL)" error for the last couple of weeks. The same problem occurs with "make menuconfig".
While I can't quite divine which terminal you're talking about (though I suspect gnome-terminal), if it works with 'su -', it's INVALID.
Yes, please retry with "su -"