When you exceed the configured memory by requesting larger phys mem guaranteed the validation blocks you correctly from saving the VM, the Resourca Allocation tab is highlighted with red box, and teh hover popup with error message is there, but the actual Physical Memory Guaranteed field is missing the red border
Verify with: Software version:4.2.0-0.0.master.20170917124606.gita804ef7.el7.centos Attached screenshot
Created attachment 1330168 [details] screenshot with fix
This bugzilla is included in oVirt 4.2.0 release, published on Dec 20th 2017. Since the problem described in this bug report should be resolved in oVirt 4.2.0 release, published on Dec 20th 2017, it has been closed with a resolution of CURRENT RELEASE. If the solution does not work for you, please open a new bug report.