Impossible de démonter / home pendant la fermeture de l'arc linux

J'ai installé l'arc sur mon système plusieurs fois et tout a bien fonctionné, mais depuis la dernière installation, j'ai vu des messages: Failed unmounting /home. et Failed unmounting /run/user/1000. pendant la procédure d'arrêt ou de redémarrage. J'ai cherché des forums similaires pour des discussions similaires et n'ai rien trouvé pour résoudre ce problème malgré plusieurs conversations sur ce sujet.

Voici la journalctl -p 0..3 -xn :

 -- Logs begin at Sun 2015-08-02 15:24:27 IST, end at Tue 2015-08-04 21:29:57 IST. -- Aug 04 17:26:59 lenovo systemd-logind[315]: Failed to abandon session scope: Transport endpoint is not connected Aug 04 17:26:59 lenovo systemd[1]: Failed unmounting /home. -- Subject: Unit home.mount has finished shutting down -- Defined-By: systemd -- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel -- -- Unit home.mount has finished shutting down. Aug 04 17:26:59 lenovo systemd[1]: Failed unmounting /run/user/1000. -- Subject: Unit run-user-1000.mount has finished shutting down -- Defined-By: systemd -- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel -- -- Unit run-user-1000.mount has finished shutting down. -- Reboot -- Aug 04 19:34:30 lenovo dhcpcd[320]: enp1s0: ipv6nd_sendrsprobe: sendmsg: Cannot assign requested address Aug 04 19:34:40 lenovo dhcpcd[320]: enp1s0: DHCP lease expired Aug 04 19:55:31 lenovo systemd-logind[339]: Failed to abandon session scope: Transport endpoint is not connected Aug 04 19:55:31 lenovo systemd[1]: Failed unmounting /home. -- Subject: Unit home.mount has finished shutting down -- Defined-By: systemd -- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel -- -- Unit home.mount has finished shutting down. Aug 04 19:55:31 lenovo systemd[1]: Failed unmounting /run/user/1000. -- Subject: Unit run-user-1000.mount has finished shutting down -- Defined-By: systemd -- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel -- -- Unit run-user-1000.mount has finished shutting down. -- Reboot -- Aug 04 21:25:48 lenovo dhcpcd[309]: enp1s0: DHCP lease expired Aug 04 21:26:46 lenovo dhcpcd[309]: enp1s0: DHCP lease expired 

Voici la sortie de cat /etc/fstab :

 # # /etc/fstab: static file system information # # <file system> <dir> <type> <options> <dump> <pass> # /dev/sda3 UUID=d98988d2-4106-4f72-bc14-492d1acbb4fb / ext4 rw,relatime,data=ordered 0 1 # /dev/sda1 UUID=166C-1970 /boot vfat rw,relatime,fmask=0022,dmask=0022,codepage=437,iocharset=iso8859-1,shortname=mixed,errors=remount-ro 0 2 # /dev/sda4 UUID=75c1fdba-3038-451e-ba11-adeb18ac99dc /home ext4 rw,relatime,data=ordered 0 2 # /dev/sda2 UUID=89adf58d-e21e-4d12-8bd6-2d44314daa55 none swap defaults 0 0 

et voici la sortie de lsblk :

 NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT sda 8:0 0 465.8G 0 disk ├─sda1 8:1 0 1G 0 part ├─sda2 8:2 0 4G 0 part [SWAP] ├─sda3 8:3 0 30G 0 part / └─sda4 8:4 0 430.8G 0 part /home sr0 11:0 1 1024M 0 rom 

Je n'ai aucune idée de ce que ces messages signifient ou autrement j'aurais certainement cherché plus à ce sujet. Je vous remercie.