vm-builder 0.12.3-0ubuntu1 crashes and causes loop devices to be stuck

[Chris Cheney]

I am having problems getting vm-builder to build an image for me. I'm not sure if I am even using it correctly, but after the crashes it seems to eat a loop file for each run corresponding to the disk image file. I unmount the various dirs that are mounted and that frees up two of the loop files but the third doesn't appear to be mounted. Also, I can't delete it with losetup as it claims "Device or resource busy" and nothing shows up in mount as still being mounted.

[Yann Hamon (yannh)]

Sorry if I cant add much infos, but I had the same issue on lucid a few days ago. Ps -ef would show all the loop devices (8 of them as far as I can remember).

If that helps chris, vmbuilder wont work as long as those loop devices are used - but if you reboot (I know...) it will clear the loop devices and vmbuilder will work. Just don't ctrl+c too much when running vmbuilder as long as this isnt solved...

[Chris Cheney (ccheney)]

I didn't use ctrl-c vm-builder just bombed out probably due to other bugs and didn't clean up the resulting mess, and I couldn't figure out how to clean it up later without rebooting.

[GeekSmith (lixo-geeksmith)]

I'm seeing this any time vmbuilder fails. If it fails more than a few times, I run out of loopback devices and can't build anything more. Here are the loopback devices it leaves for a VM with two hard disks:

I'm able to clean up the loopback devices manually, but it's quite a pain:
aaron.smith@asmith ~/dvp/vm % sudo losetup -a
/dev/loop0: [0801]:678634 (/tmp/tmpZjs7XP)
/dev/loop1: [0801]:678638 (/tmp/tmpFfS6q9)
aaron.smith@asmith ~/dvp/vm % sudo losetup -d /dev/loop0
loop: can't delete device /dev/loop0: Device or resource busy
aaron.smith@asmith ~/dvp/vm % sudo kpartx -d /dev/loop0
aaron.smith@asmith ~/dvp/vm % sudo losetup -d /dev/loop0
aaron.smith@asmith ~/dvp/vm % sudo losetup -a
/dev/loop1: [0801]:678638 (/tmp/tmpFfS6q9)

-- OK, one down. The last one is a litte more painful:
aaron.smith@asmith ~/dvp/vm % sudo dmsetup table
loop1p1: 0 15622984 linear 7:1 63
aaron.smith@asmith ~/dvp/vm % sudo kpartx -dv /dev/mapper/loop1p1
aaron.smith@asmith ~/dvp/vm % sudo losetup -d /dev/mapper/loop1p1
aaron.smith@asmith ~/dvp/vm % sudo losetup -a
aaron.smith@asmith ~/dvp/vm %

If a person is trying to automate creation of a VM in a build process, this becomes burdensome.