Re: [Qemu-discuss] Supported hypervisors running VMs in nested VM

[Bandan Das]

...
> Windows 2012 / 2016 technical preview 3
> --------------------------------------------------------
> The installation via the "default" method of Add/Remove Features does
> not work. Hyper-V displays the error message "A hypervisor is already
> running".
> 
> This check can be skipped by using a different method of installation
> (from PowerShell):
> Enable-WindowsOptionalFeature –Online -FeatureName Microsoft-Hyper-V
> –All -NoRestart
> 
> This results in (again) the server booting up, but being unable to run
> any guest VMs. The error message is less clear then that in 2008, just
> "The Virtual Machine Management Service failed to start the virtual
> machine 'New Virtual Machine' because one of the Hyper-V components is
> not running (Virtual machine ID
> 0C063B29-249A-41C8-8A5B-6D4D2E37EF7C)."
> is what I could find.
> 
> Other
> --------
> Just to verify that "nesting" is actually working, I've also installed
> a Ubuntu 15.10 VM and installed Qemu on it.
> This combination CAN successfully run a VM.
> 
> I've also installed VirtualBox on one of the Windows VMs. This
> VirtualBox instance is also capable of running virtual machines.
> According to the icon in the bottom right, VirtualBox IS using the
> hardware virtualization.
> 
> Is this a problem specific to Hyper-V? Is there a method to get

Nesting a Hyper-V L1 hypervisor is largely untested. But one of the problems I 
recollect is that Hyper-V doesn’t like running in a virtualized environment. It 
checks the “hypervisor” feature flag that Qemu exports. You could try running 
qemu with “-cpu  host,-hypervisor” or something similar and see if it makes any 
difference. I suspect there would be other roadblocks though, this is just one 
of them.



> Hyper-V working including running guests? I know for a fact that
> VMWare Workstation / ESX is able to run Hyper-V fully, so it should

Yes, IIRC one of the things ESX does is hide the hypervisor flag specifically 
for Hyper-V. 

Bandan

> not be completely impossible (but I dislike VMWare for different
> reasons).
> 
> My Qemu command line (generated by virt-manager). Except for disks and
> domain names, all are identical:
> 
> qemu-system-x86_64 -enable-kvm -name Windows_2008_R2 -S -machine
> pc-i440fx-vivid,accel=kvm,usb=off -cpu
> SandyBridge,+invtsc,+osxsave,+pcid,+pdcm,+xtpr,+tm2,+est,+smx,+vmx,+ds_cpl,+monitor,+dtes64,+pbe,+tm,+ht,+ss,+acpi,+ds,+vme
> -m 2048 -realtime mlock=off -smp 2,sockets=2,cores=1,threads=1 -uuid
> 54a8f3a3-66c2-45a5-a280-ecf7019a67fa -no-user-config -nodefaults
> -chardev 
> socket,id=charmonitor,path=/var/lib/libvirt/qemu/Windows_2008_R2.monitor,server,nowait
> -mon chardev=charmonitor,id=monitor,mode=control -rtc
> base=localtime,driftfix=slew -global kvm-pit.lost_tick_policy=discard
> -no-hpet -no-shutdown -global PIIX4_PM.disable_s3=1 -global
> PIIX4_PM.disable_s4=1 -boot strict=on -device
> ich9-usb-ehci1,id=usb,bus=pci.0,addr=0x6.0x7 -device
> ich9-usb-uhci1,masterbus=usb.0,firstport=0,bus=pci.0,multifunction=on,addr=0x6
> -device ich9-usb-uhci2,masterbus=usb.0,firstport=2,bus=pci.0,addr=0x6.0x1
> -device ich9-usb-uhci3,masterbus=usb.0,firstport=4,bus=pci.0,addr=0x6.0x2
> -device virtio-serial-pci,id=virtio-serial0,bus=pci.0,addr=0x5 -drive
> file=/sub/kvm/Windows_2008_R2.qcow2,if=none,id=drive-ide0-0-0,format=qcow2,cache=unsafe,aio=threads
> -device ide-hd,bus=ide.0,unit=0,drive=drive-ide0-0-0,id=ide0-0-0,bootindex=1
> -drive 
> file=/sub/ISO/en_windows_server_2008_r2_with_sp1_x64_dvd_617601.iso,if=none,id=drive-ide0-0-1,readonly=on,format=raw
> -device ide-cd,bus=ide.0,unit=1,drive=drive-ide0-0-1,id=ide0-0-1
> -netdev tap,fd=24,id=hostnet0 -device
> rtl8139,netdev=hostnet0,id=net0,mac=52:54:00:7b:d7:d2,bus=pci.0,addr=0x3
> -chardev pty,id=charserial0 -device
> isa-serial,chardev=charserial0,id=serial0 -chardev
> spicevmc,id=charchannel0,name=vdagent -device
> virtserialport,bus=virtio-serial0.0,nr=1,chardev=charchannel0,id=channel0,name=com.redhat.spice.0
> -device usb-tablet,id=input0 -spice
> port=5903,addr=127.0.0.1,disable-ticketing,seamless-migration=on
> -device 
> qxl-vga,id=video0,ram_size=67108864,vram_size=67108864,vgamem_mb=16,bus=pci.0,addr=0x2
> -device intel-hda,id=sound0,bus=pci.0,addr=0x4 -device
> hda-duplex,id=sound0-codec0,bus=sound0.0,cad=0 -chardev
> spicevmc,id=charredir0,name=usbredir -device
> usb-redir,chardev=charredir0,id=redir0 -chardev
> spicevmc,id=charredir1,name=usbredir -device
> usb-redir,chardev=charredir1,id=redir1 -chardev
> spicevmc,id=charredir2,name=usbredir -device
> usb-redir,chardev=charredir2,id=redir2 -chardev
> spicevmc,id=charredir3,name=usbredir -device
> usb-redir,chardev=charredir3,id=redir3 -device
> virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x7 -msg timestamp=on
> 
> Thank you in advance for response.
> 
> Sincerely,
> Roel Brook
>