is_kdbus_available always returns false. The reason is that for KDBUS_CMD_BUS_MAKE there must be KDBUS_ITEM_MAKE_NAME and KDBUS_ITEM_BLOOM_PARAMETER. According to kdbus_cmd_bus_make() they are mandatory.
This is already fixed in kdbus.ko. Please use the tree at github: https://github.com/systemd-devs/kdbus (make sure to use the correct branch, v4.0 probably)
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