[vfio-users] cannot boot windows guest after update

[Torbjorn Jansson]

On 2016-05-05 00:32, thibaut noah wrote:
> By modifying my xml i managed to go into repair mode, trying to just run
> windows 10 get me a blue screen with inaccessible boot device code.
> Looking into that.
>
> 2016-05-05 0:15 GMT+02:00 thibaut noah <thibaut.noah at gmail.com>:
>
>> Hi ! So i use the repair upgrade feature of windows 10 enterprise to
>> update to the new build.
>> Since it was bugging on the vm i booted in native in order to do the
>> update.
>> I reinstalled grub afterwards to be able to boot linux and now i can't
>> launch windows anymore from qemu.
>> So, what happened? is it a problem with the drivers not properly set
>> because i did the update in native?
>>
>

if you booted the "vm" native and did the upgrade, the upgrade process 
probably screwed up your boot drivers.
i'm not so sure that booting a vm native is a good idea, especially with 
windows.

assuming the problem is just a few missing drivers and you can get into 
recovery mode on the vm, then you can try the dism trick and inject boot 
drivers to an offline copy of windows.

this can be a handy trick if you for example move a harddrive from one 
computer to another and get inaccessible boot device and dont want to 
reinstall.

the basic process is something like this:
boot to recovery and make sure you can access both the windows 
installation and the drivers needed to boot.
open up a cmd window and take a look at the command line options for dism.
if i remeber correctly you need to specify where the offline windows 
copy is and where the drivers are located.
you should be able to specify a root folder or similar where the drivers 
are and get it to inject all drivers in that folder tree.

then reboot an hope for the best.