I just installed esxi6u2 on top of qemu-2.7.0, following https://allyourco.de/running-vmware-esxi-under-qemu-kvm/
I'm using virt-manager-1.3.2 for qemu management.
Now I tried to deploy the vcsa, it got pushed to the esxi host and then I got a PSOD with the error:"PCPU 0 locked up. Failed to ack TLB invalidate" I suspect it's an issue with about multiple sockets instead of one socket with multiple cores.
I have changed the cpu setting to current allocation: 2, topoligy: 1 socket, 2 cores, 1 thread. This seems to work.
Another issue I encountered is that esxi refuses to boot the vcsa appliance, complaining about: "you are running vmware esx through an incompatible hypervisor" and vmware KB 2108724 specifies that the vm's config has to be altered to add vmx.allowNested=TRUE for the nested VM to run.
If you have access to powercli, then you can set this new adv. setting the following way:
connectVIserver [ESXi host]
get-vm [vm name] | new-advancedsetting -name vmx.allowNested -value 'TRUE'