[CentOS] kpartx can not detach

Wed Mar 7 18:35:55 UTC 2018
Jim Perrin <jperrin at centos.org>

On 03/07/2018 04:48 AM, Leon Fauster wrote:
> OS: EL6 - sometimes I use 
> kpartx -a /mnt/.../lvdisk.img 
> to map the partitions and mount them via 
> /dev/mapper/loop0pX
> After using the disk (unmounting it) I noticed that 
> detaching such mapping via kpartx -d does not result 
> in freeing up the loop devices. Results: System reboots 
> shows that the filesystem where lvdisk.img is located 
> can't be unmounted. 
> lsof, fuser, ps does not show any usage. Even removing the 
> device node via 
> dmsetup remove /dev/mapper/loop0pX
> does not help. Trying to unmount the underlying filesystem 
> still shows /mnt: device is busy.
> Any other suggestions would be greatly appreciated!

Do you have an open shell/terminal session hanging out in the /mnt
directory you used?

Jim Perrin
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