Could you please attach the logs in /var/log/dist-upgrade/* ? There is a known race condition in the lock file operation, but it should not be easy to trigger. I have not debugged it in detail, but it basicly its the problem that apt runs dpkg in various runs and when one dpkg exists it gives up the lock and when the next one starts it takes it again. In between there is a lock-less time.
Thanks for your bugreport.
Could you please attach the logs in /var/log/ dist-upgrade/ * ? There is a known race condition in the lock file operation, but it should not be easy to trigger. I have not debugged it in detail, but it basicly its the problem that apt runs dpkg in various runs and when one dpkg exists it gives up the lock and when the next one starts it takes it again. In between there is a lock-less time.