http://bugzilla.suse.com/show_bug.cgi?id=931049 --- Comment #3 from Marcus Schaefer --- you can disable the runtime check via export KIWI_IGNORE_OLD_MOUNTS=1 The buildservice can do that in general when it builds images with kiwi However the question is still valid why other processes not related to kiwi in any case have a mount reference to something kiwi mounted and why do these processes block the owner of the mount to correctly umount it I'm sorry but in kiwi all I can do is mount and correctly umount once I'm sure I'm not busy anymore. If some other process or the kernel thinks different about this I'm lost We implemented the runtime check to be able to detect the situation but I still can't tell why this appears. The link in the initial comment shows a successful build though If you run parallel image builds in a chroot on the same host the check is correct and also makes sense. Because that could really cause mount conflicts and was never supported by kiwi. parallel image builds are only supported in VMs or containers because they really encapsulated host resources properly for image builds If it's not a problem for the buildservice to leave the buildsystem with a busy proc, sys or some other mount process you can safely export the variable above which will disable the runtime check Adding Adrian to CC -- You are receiving this mail because: You are on the CC list for the bug.