Reviewed: https://review.opendev.org/c/openstack/neutron/+/788714 Committed: https://opendev.org/openstack/neutron/commit/b993ebb407208bf04a7957a3d15c9ac482a1dd5c Submitter: "Zuul (22348)" Branch: master
commit b993ebb407208bf04a7957a3d15c9ac482a1dd5c Author: Sebastian Lohff <[email protected]> Date: Wed Apr 28 14:53:46 2021 +0200 Fix dynamic segment allocation race condition When two segments are concurrently created this could have resulted in both threads creating a segment, thus resulting in two segments with different segmentation ids. To prevent this we now introduce a new unique constraint onto the networksegments table, which requires (network_id, network_type, physical_network) to be unique, which allows only a single segment with a single segmentation id to exist per combination of these three values. With the constraint in place a DB error will be thrown, which will cause allocate_dynamic_segment() to be executed again and this time it will find the already existing segment. To make sure that no additional DB objects are created when segment creation failed we need to put all of the allocation code into a DB transaction. Change-Id: I407ae88d69ed971bf8d9a9b79120366f33bb56fd Closes-Bug: #1791233 ** Changed in: neutron Status: In Progress => Fix Released -- You received this bug notification because you are a member of Yahoo! Engineering Team, which is subscribed to neutron. https://bugs.launchpad.net/bugs/1791233 Title: Redundant dynamic partial segments was allocated for the same network and physical_network Status in neutron: Fix Released Bug description: We are expected to get the same partial segment allocated for specified network and physical_network by calling neutron.plugins.ml2.managers.TypeManager.allocate_dynamic_segment. but there is a race condition: 1. Two processes call allocate_dynamic_segment function with specified network and physical_network simultaneously. 2. Two processes both retrieve no allocated segment, and both allocate a new partial segment indeed. 3. Two partial dynamic segments was allocated for the same network and physical_network. To manage notifications about this bug go to: https://bugs.launchpad.net/neutron/+bug/1791233/+subscriptions -- Mailing list: https://launchpad.net/~yahoo-eng-team Post to : [email protected] Unsubscribe : https://launchpad.net/~yahoo-eng-team More help : https://help.launchpad.net/ListHelp
