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Hi Paul,

I have now got the 8.1.0-rc2 installed and working. I tried removing the Unplug value you suggested and then rebooting but that value just seems to reappeared and the drivers still seem to be in use - they are reported by driverquery and the devices appear in 'Computer Management'. I have also tried removing the drivers with Dism and changing the Unplug value after removing the drivers with Dism which both resulted in an unbootable system like before.

I'll try the other suggestions people here made and see if those are any help but is there anything you would recommend or some information I can find to help debug this? I only built the 8.1.0-rc2 code but I'm happy to retry with the code from master if there's been any changes in this area since the RC.

Cheers,

Joel

From: Paul Durrant <Paul.Durrant@xxxxxxxxxx>
Sent: 15 September 2015 15:40
To: Joel Noyce-Barnham; win-pv-devel@xxxxxxxxxxxxxxxxxxxx
Subject: RE: PV Drivers Offline Removal

Thanks. It would be good to confirm it actually works J

Paul

From: Joel Noyce-Barnham [mailto:joel.noyce-barnham@xxxxxxxxxxx]
Sent: 15 September 2015 15:33
To: Paul Durrant; win-pv-devel@xxxxxxxxxxxxxxxxxxxx
Subject: Re: PV Drivers Offline Removal

Paul,

Thanks for the reply. The version of the drivers I am using doesn't seem to have added that key to the registry so I will try the same tests with the 8.1.0-rc2 code which contains your recent changes to the unplug code. I will let you know how I get on.

Cheers,
Joel

From: Paul Durrant <Paul.Durrant@xxxxxxxxxx>
Sent: 15 September 2015 09:59
To: Joel Noyce-Barnham; win-pv-devel@xxxxxxxxxxxxxxxxxxxx
Subject: RE: PV Drivers Offline Removal

Joel,

Offline removal should be quite possible. The thing that needs to be cleaned up to make sure the image will reboot are the ‘unplug’ values that are used early on in boot to request unplug of emulated devices in QEMU. Look under HKLM/system/currentcontrolset/services/xen and you should see a key called ‘Unplug’. If you delete that key then the next reboot should use emulated devices and so should be fine with no PV drivers.

Cheers,

Paul

From: win-pv-devel-bounces@xxxxxxxxxxxxxxxxxxxx [mailto:win-pv-devel-bounces@xxxxxxxxxxxxxxxxxxxx] On Behalf Of Joel Noyce-Barnham
Sent: 14 September 2015 18:21
To: win-pv-devel@xxxxxxxxxxxxxxxxxxxx
Subject: [win-pv-devel] PV Drivers Offline Removal

Hi All,

We are currently using the GPLPV drivers but are hoping to move to the new Xen WINPV drivers as they are actively developed and have some new features which we are interested in. We currently have a process where VMs can be moved from our Xen hypervisor into EC2. This process relies on the fact that we are able to remove the drivers from an offline image. Previously we have been removing the drivers successfully by converting the disk images to a VHD file, using Dism to remove the drivers (https://technet.microsoft.com/en-GB/library/dd744355%28v=ws.10%29.aspx) and then importing the resulting VHD into EC2. This works with the GPLPV drivers but with the new WINPV drivers it creates an unbootable image (the import into EC2 fails and the image can also not be booted on the original hypervisor).

I have found some previous posts on this mailing list (http://lists.xenproject.org/archives/html/win-pv-devel/2015-03/msg00076.html) discussing removing the drivers and I am able to successfully remove the drivers from an online image but sadly our process requires that this removal be performed offline.

I am just wondering if anyone else is using Dism in windows to remove the PV drivers from an offline image? Or if anyone else has successfully removed the WINPV drivers from an offline image at all? Any pointers anyone can give would be appreciated. The only way we have so far found to make the image boot after removing the drivers with Dism is by manual modification of a large number of registry keys which seems like a far from ideal solution.

Thanks for any help,
Joel

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Re: [win-pv-devel] PV Drivers Offline Removal