Comment 9 for bug 1331406

A temporary workaround while waiting for the patch to land and be released is to set the provider back to keystone.token.providers.pki.Provider or keystone.token.providers.uuid.Provider, in the Keystone.conf for the provider setting: https://github.com/openstack/keystone/blob/e03c7af51c/etc/keystone.conf.sample#L1314 (thanks to Morgan for the helpful tips!). I tested with PKI and UUID and it does resolve the login issue.