https://communities.vmware.com/docs/DOC-8970

You can expose full CPU virtualization to the guest operating system so that applications that require hardware virtualization can run on virtual machines without binary translation or paravirtualization.

Prerequisites

• Verify that the virtual machine compatibility is ESXi 5.1 and later.
• Intel Nehalem Generation (Xeon Core i7) or later processors or AMD Opteron Generation 3 (Greyhound) or later processors.
• Verify that Intel VT-x or AMD-V is enabled in the BIOS so that hardware assisted virtualization is possible.
• Required Privileges: Virtual machine.Configuration.Settings set on the vCenter Server system.

Procedure

• Right-click the virtual machine and select Edit Settings
• To locate a virtual machine, select a datacenter, folder, cluster, resource pool, host, or vApp.
• Click the Related Objects tab and click Virtual Machines.
• On the Virtual Hardware tab, expand CPU, and select Expose hardware-assisted virtualization to guest OS.
• Click OK.
• The Manage tab refreshes, and the Nested Hypervisor CPU option shows Enabled.