[ubuntu] Windows 10 qemu/kvm guest win/fails...

Starting a thread on the successes or otherwise with Windows 10 qemu/kvm guests, please share your results/recommendations....

I current run Windows 7 Ultimate in a qemu/kvm guest using legacy Seabios...this is primarily my corp desktop. I qualified for the free upgrade to Windows 10 so I've been playing around with various solutions pre and post official release.

Windows 10 Pre-Release (Insider Previews / Technical Previews)

• Very early Tech Prev seemed to work fine using the available virtio drivers from redhat.
• However the later Insider Preview releases caused me some headaches
  
  • Various forum searches showed others having similar issues with solutions ranging from setting CPU types to 'kvm64' to using 'Virtio SCSI' controllers.
  • I personally had success after changing disk controllers (https://me.m01.eu/blog/2015/03/windo...kvm-and-iscsi/)

Windows 10 Official-Release (clean installation from .iso file)

• Used the media creation tool MS released to download the installation media (.iso)
• Used the latest OVMF build from here https://www.kraxel.org/repos/jenkins/edk2/
• Configured the guest to copy my host CPU specs and set the topology for 1x socket, 2x cores, 2x threads. (lshw: Intel(R) Core(TM) i7-4790S CPU @ 3.20GHz)
• Used the IDE bus for the windows .iso installation media and the virtio drivers (grabbed the latest from https://fedoraproject.org/wiki/Windo...irect_download)
  
  • NOTE: I used the win8.1 amd64 virtio drivers, no complaints or issues noticed thus far
  
  
• This pretty much gives me a functional Windows 10 qemu/kvm guest which seems as per-formant as my Windows 7 legacy.

The problem is you can't just activate the Windows 10 clean installation using the Windows 7 Product Key...Microsoft want you to upgrade your earlier version to qualify for the free Windows 10 copy (see http://www.howtogeek.com/224342/how-...ll-windows-10/)

Windows 10 Official-Release (upgrade from earlier version of windows)

• Firstly, the Windows 10 upgrade tool in the taskbar of my Windows 7 guest said my hardware wasn't compatible because of the 'Redhat Display Adapter'
  
  • You have to force the issue here by using the media creation tool and creating either an .iso (as per above) or a USB installer, either is fine just execute the setup program from the media to bypass the upgrade tool
  
  
• So this is where I start getting issues

• So I attempted a clean install of Windows 7 first, turns out that Win7 boot is buggy when using OVMF as it consistently powers off shortly after the windows boot logo appears. I can't find the trigger for the bug but by altering the CPU config for the guest you can get a successful boot i.e. switch the processor type after each failed boot...however rebooting after a successful boot seems to causes the issue again...I just keep switching guest processor settings to workaround this.
  
• Anyways for this test I persisted, completed the install and got to Win7 desktop...applied the virtio drivers etc but didn't do any windows updates.
  
• I used the .iso install media I created from the prior tests and ran the executable
  
• The installer does its stuff, completes its first pass to 100% (copying files I think)...then it reboots...
  
• The (re)boot up looks like windows 10 but then I get a black screen and all activity ceases i.e. no io, cpu cycles etc.
  
• I force a restart which (re)boots into Windows 7 and the Windows 10 Upgrade dialogue appears saying "The installation failed in the SAFE_OS phase with an error during BOOT operation."

Anyone seen this themselves and even better has anyone overcome this problem?