MarsSeed [1] filed a deletion request for kdbus-ck [2]: The kdbus out-of-tree Linux module has not been mainlined to the proposed Linux 4.3. Instead, it seems it has been discontinued after 2017. [a] [b] This package was last updated in 2015 and was compatible with Linux 4.3. I think it is better to delete it, as it is defunct and cannot even be built. [a] https://github.com/systemd/kdbus [b] https://github.com/gregkh/kdbus [1] https://aur.archlinux.org/account/MarsSeed/ [2] https://aur.archlinux.org/pkgbase/kdbus-ck/