---
fixes:
  - |
    [`bug 1878938 <https://bugs.launchpad.net/keystone/+bug/1878938>`_]
    Previously when a user used to have system role assignment and tries to delete
    the same role, the system role assignments still existed in system_assignment
    table. This causes keystone to return `HTTP 404 Not Found` errors when listing
    role assignments with names (e.g., `--names` or `?include_names`).

    If you are affected by this bug, you must remove stale role assignments
    manually. The following is an example SQL statement you can use to fix the
    issue, but you should verify it's applicability to your deployment's SQL
    implementation and version.

    SQL:
         - delete from system_assignment where role_id not in (select id from role);