Gitian VM creation fails on Ubuntu 16.x machines in the unmount step
There have been reports that creating Gitian VMs on Ubuntu 16.x machines fails with error messages like:
2016-10-06 15:11:05,650 INFO : umount: /tmp/tmpxmUBiv/: target is busy
2016-10-06 15:11:05,651 INFO : (In some cases useful info about processes that
2016-10-06 15:11:05,651 INFO : use the device is found by lsof(8) or fuser(1).)
2016-10-06 15:11:05,651 ERROR : Process (['umount', '/tmp/tmpxmUBiv/']) returned 32. stdout: , stderr: umount: /tmp/tmpxmUBiv/: target is busy
(In some cases useful info about processes that
use the device is found by lsof(8) or fuser(1).)
Traceback (most recent call last):
File "/usr/local/bin/vmbuilder", line 24, in <module>
cli.main()
File "/usr/local/lib/python2.7/dist-packages/VMBuilder/contrib/cli.py", line 228, in main
hypervisor.install_os()
File "/usr/local/lib/python2.7/dist-packages/VMBuilder/hypervisor.py", line 70, in install_os
self.call_hooks('install_bootloader', self.chroot_dir, self.disks)
File "/usr/local/lib/python2.7/dist-packages/VMBuilder/distro.py", line 69, in call_hooks
self.cleanup()
File "/usr/local/lib/python2.7/dist-packages/VMBuilder/distro.py", line 44, in cleanup
self._cleanup_cbs.pop(0)()
File "/usr/local/lib/python2.7/dist-packages/VMBuilder/disk.py", line 409, in umount
run_cmd('umount', self.mntpath)
File "/usr/local/lib/python2.7/dist-packages/VMBuilder/util.py", line 120, in run_cmd
raise VMBuilderException, "Process (%s) returned %d. stdout: %s, stderr: %s" % (args.__repr__(), status, mystdout.buf, mystderr.buf)
VMBuilder.exception.VMBuilderException: Process (['umount', '/tmp/tmpxmUBiv/']) returned 32. stdout: , stderr: umount: /tmp/tmpxmUBiv/: target is busy
(In some cases useful info about processes that
use the device is found by lsof(8) or fuser(1).)
qemu-img: target-wheezy-i386.qcow2: Could not open 'base-wheezy-i386.qcow2': No such file or directory
i386 wheezy VM creation failed
And, indeed, for some reason there seem to be still resources used:
/dev/dm-12 on /tmp/tmp9k2g2E type ext3 (rw,relatime,data=ordered)
/dev/sda1 on /tmp/tmp9k2g2E/tmp/vmbuilder-grub/tmpUE0GzK type ext4 (rw,relatime,errors=remount-ro,data=ordered)