Red Hat Bugzilla – Bug 1478147
multiple asynchronous mirror device failures lead to deadlocks
Last modified: 2017-10-12 10:50:48 EDT
I assume the issue here is - 'dmeventd' protects against 'failure' of standard running mirror.
As soon as old mirror is 'upconverting' there is nothing yet to resolve blocked mirror in upconversion (aka mirror on mirror)
This is nontrivial to resolve, since there is not much devel being done with old mirrors....