Comment 3 for bug 1896463

> How frequently could the problem be reproduced? Once in 10 attempts or 100 attempts?

Very rare because the racy section is short.

> Also the _move_claim[6] first updates the migration object and then claims the pci devices. So I don't see how this can race with the _update_available_resource() run.

Problem is not in the claim step, but in the free step. Currently clean_usage() part isn't protected from below:

3075 instance.save()
3076 instance.drop_migration_context()