From 81928e20d592ff7a30caf4c636cb851965a39b31 Mon Sep 17 00:00:00 2001
From: "Richard W.M. Jones" <rjones@redhat.com>
Date: Fri, 5 Dec 2014 15:04:03 +0000
Subject: [PATCH] v2v: Add documentation about what to do about BSOD 0x0000007B
 (RHBZ#1161333).

After a very long and trying episode with a Windows guest that refused
to boot after conversion, we managed to successfully boot it by
disabling Windows Group Policy.  It appears that Group Policy
prevented the virtio driver from being used.

Document this in the manual.

(cherry picked from commit be73b1750f3ce52ea137014083ed51d3b64f53a5)
---
 v2v/virt-v2v.pod | 56 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 56 insertions(+)

diff --git a/v2v/virt-v2v.pod b/v2v/virt-v2v.pod
index 5c97984..5f4d42e 100644
--- a/v2v/virt-v2v.pod
+++ b/v2v/virt-v2v.pod
@@ -623,6 +623,62 @@ below.
  Windows        Drivers are installed from /usr/share/virtio-win
                 if present
 
+=head1 WINDOWS
+
+=head2 Boot failure: 0x0000007B
+
+This boot failure is caused by Windows being unable to find or load
+the right disk driver (eg. C<viostor.sys>).  If you experience this
+error, here are some things to check:
+
+=over 4
+
+=item *
+
+First ensure that the guest boots on the source hypervisor before
+conversion.
+
+=item *
+
+Check you have the Windows virtio drivers available in
+C</usr/share/virtio-win>, and that virt-v2v did not print any warning
+about not being able to install virtio drivers.
+
+On S<Red Hat Enterprise Linux 7>, you will need to install the signed
+drivers available in the C<virtio-win> package.  If you do not have
+access to the signed drivers, then you will probably need to disable
+driver signing in the boot menus.
+
+=item *
+
+Check that you are presenting a virtio-blk interface (B<not>
+virtio-scsi and B<not> ide) to the guest.  On the qemu/KVM command
+line you should see something similar to this:
+
+ ... -drive file=windows-sda,if=virtio ...
+
+In libvirt XML, you should see:
+
+ <target dev='vda' bus='virtio'/>
+
+=item *
+
+Check that Windows Group Policy does not prevent the driver from being
+installed or used.  Try deleting Windows Group Policy before
+conversion.
+
+=item *
+
+Check there is no anti-virus or other software which implements Group
+Policy-like prohibitions on installing or using new drivers.
+
+=item *
+
+Enable boot debugging and check the C<viostor.sys> driver is being
+loaded.
+
+=back
+
 =head1 NETWORKS AND BRIDGES
 
 Guests are usually connected to one or more networks, and when
-- 
1.8.3.1