Am 07.03.2018 um 19:35 schrieb Jim Perrin jperrin@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?
With some heuristic I got following results (briefly):
Jumping into the image/file directory and adding the partition map (kpartx -a) and removing it (kpartx -d) works!
So the output of losetup between this two activities shows:
losetup -a /dev/loop0: [0821]:130822 (kvm-system-centos6_x86_64-devel-lv_vm_intern_spare.img)
but when adding the partition map with an absolut _long_ path detaching/deleting the map doesn't work.
losetup -a /dev/loop0: [0821]:130822 (/mnt/pool/VirtLibrary/3-live/kvm-system-centos6_x86_64-devel-l*)
shortening the path and adding the partition map with an absolut path and removing it works again.
losetup -a /dev/loop0: [0821]:130822 (/mnt/kvm-system-centos6_x86_64-devel-lv_vm_intern_spare.img)
So, is kpartx or the underlying loop handle limited to a 64 character long file pointer?
Anyway, at least I can work around it ...
-- LF