AttributeError: 'Mount' object has no attribute 'mount_dir'

[dereckson]

For an unidentified reason, it wasn't possible to unmount the bootstrap volume (lsof / fuser didn't show anything using the disk).

In such scenario, the code logic tries to read a non existing mount_dir attribute. The issue was reproductible.

Tested with current master code.

Here a log from our CI/CD environment to with the relevant stacktrace.

error	24-Apr-2019 16:09:27	Unmounting the bootstrap volume
error	24-Apr-2019 16:09:27	umount: /target/4a784653/root/dev: target is busy
error	24-Apr-2019 16:09:27	(In some cases useful info about processes that
error	24-Apr-2019 16:09:27	use the device is found by lsof(8) or fuser(1).)
error	24-Apr-2019 16:09:28	Command 'umount /target/4a784653/root/dev' returned non-zero exit status 32
error	24-Apr-2019 16:09:28	Traceback (most recent call last):
error	24-Apr-2019 16:09:28	  File "/bootstrap/debian-template-593/bootstrap/bootstrapvz/base/main.py", line 111, in run
error	24-Apr-2019 16:09:28	    tasklist.run(info=bootstrap_info, dry_run=dry_run)
error	24-Apr-2019 16:09:28	  File "/bootstrap/debian-template-593/bootstrap/bootstrapvz/base/tasklist.py", line 44, in run
error	24-Apr-2019 16:09:28	    task.run(info)
error	24-Apr-2019 16:09:28	  File "/bootstrap/debian-template-593/bootstrap/bootstrapvz/common/tasks/filesystem.py", line 189, in run
error	24-Apr-2019 16:09:28	    info.volume.partition_map.root.unmount()
error	24-Apr-2019 16:09:28	  File "/bootstrap/debian-template-593/bootstrap/bootstrapvz/common/fsm_proxy.py", line 39, in proxy
error	24-Apr-2019 16:09:28	    fn(**kwargs)
error	24-Apr-2019 16:09:28	  File "/usr/lib/python2.7/dist-packages/fysom/__init__.py", line 283, in fn
error	24-Apr-2019 16:09:28	    if self._before_event(e) is False:
error	24-Apr-2019 16:09:28	  File "/usr/lib/python2.7/dist-packages/fysom/__init__.py", line 318, in _before_event
error	24-Apr-2019 16:09:28	    return getattr(self, fnname)(e)
error	24-Apr-2019 16:09:28	  File "/usr/lib/python2.7/dist-packages/fysom/__init__.py", line 89, in _callback
error	24-Apr-2019 16:09:28	    return func(obj, *args, **kwargs)
error	24-Apr-2019 16:09:28	  File "/bootstrap/debian-template-593/bootstrap/bootstrapvz/base/fs/partitions/abstract.py", line 107, in _before_unmount
error	24-Apr-2019 16:09:28	    self.mounts[destination].unmount()
error	24-Apr-2019 16:09:28	  File "/bootstrap/debian-template-593/bootstrap/bootstrapvz/base/fs/partitions/mount.py", line 39, in unmount
error	24-Apr-2019 16:09:28	    log_check_call(['umount', self.mount_dir])
error	24-Apr-2019 16:09:28	  File "/bootstrap/debian-template-593/bootstrap/bootstrapvz/common/tools.py", line 14, in log_check_call
error	24-Apr-2019 16:09:28	    raise e
error	24-Apr-2019 16:09:28	CalledProcessError: Command 'umount /target/4a784653/root/dev' returned non-zero exit status 32
error	24-Apr-2019 16:09:28	Rolling back
error	24-Apr-2019 16:09:31	Unmounting the bootstrap volume
error	24-Apr-2019 16:09:31	Traceback (most recent call last):
error	24-Apr-2019 16:09:31	  File "bootstrap-vz", line 5, in <module>
error	24-Apr-2019 16:09:31	    main()
error	24-Apr-2019 16:09:31	  File "/bootstrap/debian-template-593/bootstrap/bootstrapvz/base/main.py", line 29, in main
error	24-Apr-2019 16:09:31	    dry_run=opts['--dry-run'])
error	24-Apr-2019 16:09:31	  File "/bootstrap/debian-template-593/bootstrap/bootstrapvz/base/main.py", line 141, in run
error	24-Apr-2019 16:09:31	    rollback_tasklist.run(info=bootstrap_info, dry_run=dry_run)
error	24-Apr-2019 16:09:31	  File "/bootstrap/debian-template-593/bootstrap/bootstrapvz/base/tasklist.py", line 44, in run
error	24-Apr-2019 16:09:31	    task.run(info)
error	24-Apr-2019 16:09:31	  File "/bootstrap/debian-template-593/bootstrap/bootstrapvz/common/tasks/filesystem.py", line 189, in run
error	24-Apr-2019 16:09:31	    info.volume.partition_map.root.unmount()
error	24-Apr-2019 16:09:31	  File "/bootstrap/debian-template-593/bootstrap/bootstrapvz/common/fsm_proxy.py", line 39, in proxy
error	24-Apr-2019 16:09:31	    fn(**kwargs)
error	24-Apr-2019 16:09:31	  File "/usr/lib/python2.7/dist-packages/fysom/__init__.py", line 283, in fn
error	24-Apr-2019 16:09:31	    if self._before_event(e) is False:
error	24-Apr-2019 16:09:31	  File "/usr/lib/python2.7/dist-packages/fysom/__init__.py", line 318, in _before_event
error	24-Apr-2019 16:09:31	    return getattr(self, fnname)(e)
error	24-Apr-2019 16:09:31	  File "/usr/lib/python2.7/dist-packages/fysom/__init__.py", line 89, in _callback
error	24-Apr-2019 16:09:31	    return func(obj, *args, **kwargs)
error	24-Apr-2019 16:09:31	  File "/bootstrap/debian-template-593/bootstrap/bootstrapvz/base/fs/partitions/abstract.py", line 107, in _before_unmount
error	24-Apr-2019 16:09:31	    self.mounts[destination].unmount()
error	24-Apr-2019 16:09:31	  File "/bootstrap/debian-template-593/bootstrap/bootstrapvz/base/fs/partitions/mount.py", line 39, in unmount
error	24-Apr-2019 16:09:31	    log_check_call(['umount', self.mount_dir])
error	24-Apr-2019 16:09:31	AttributeError: 'Mount' object has no attribute 'mount_dir'

[andsens]

Please post the full log + manifest for this run. Something is not adding up. How can self.mount_dir not exist on the exact same object where it existed just a few milliseconds ago?
The relevant lines are here:

bootstrap-vz/bootstrapvz/base/fs/partitions/mount.py

Lines 38 to 40 in 32e8bbc

	else:
	log_check_call(['umount', self.mount_dir])
	del self.mount_dir

del self.mount_dir is only run when the unmount is successful and no other part of the code removes that attribute.