When I had contact with Microsoft Premier Support about a SOFS (Scale Out File Server) problem they provided me with this list of hotfixes, to get all components up to the latest version.
Ensure the SOFS nodes are updated with *ALL* the Cluster recommended updates:
Recommended hotfixes and updates for Windows Server 2012 R2-based failover clusters http://support.microsoft.com/kb/2920151
Plus 4 additional ones below:
3023894 Cluster fixes for deadlock and resource time-out issues in Windows Server 2012 R2 Update 1 http://support.microsoft.com/kb/3023894/EN-US
3027115 Custom values for various MPIO timers in Windows Server 2012 R2 may not be honored http://support.microsoft.com/kb/3027115/EN-US
3022333 Hotfix to avoid a deadlock situation on a CSV file system volume on Windows Server 2012 R2 http://support.microsoft.com/kb/3022333/EN-US
2970653 A SQL Server that is running in a Hyper-V virtual machine takes a long time to restore a database to a dynamic VHD http://support.microsoft.com/kb/2970653/EN-US
All theses hotfixes can be imported to WSUS via Microsoft Update for easy distribution.
In addition to SOFS, I’ve also deployed all the cluster hotfixes to my Hyper-V Clusters.