CSCvo33873 clearly explains what you need to do!
Does upgrading the code to 8.10.142.0 resolve the issue? NO, 8.10.112.0 already has the software fix.
Does this upgrade involves CIMC? YES, you must upgrade the CIMC if it is 3.0.4d or older.
First: have you confirmed it is definitely this bug?
- "show certificate all" - no certificates are seen
- CIMC older than 3.0.4d
If so then simply following the instructions provided:
"Connect CIMC. Enable CIMC connectivity on the controller, using "imm" commands. Browse to the CIMC interface. Find the FlexFlash, and manually enable HyperVisor in the "Enable/Disable Virtual Disk(s)" action. See:
http://www.cisco.com/c/en/us/td/docs/wireless/controller/technotes/troubleshooting/trb-guide-wlc-5520-8540.html#pgfId-1309804
Then perform a full HUU install of CIMC 3.0.4d (or whatever the latest supported CIMC is, for the 5520/8540.)
Contact TAC if further assistance is needed."
Like it says - if you still don't know how to do that, or it's not that bug, then you need to contact Cisco TAC.
