I have some knowledge with windows and might be able to help
SetupCopyOEMInf is the right API
And it should be possible to track it's whereabouts using filemon and
regmon.
I would have also investigate more into pkgmgr.exe which sounds as a
possibly possible solution (from its description)
Another possible source of info is through the administration guide. I
know it's possible to sysprep a machine with additional drivers for later
discovery by the PnP mechanism and the same mechanism used there might be
useful here as well
BTW - storage pose additional complexity if you want to boot directly from
the new driver (like in the case of moving to virtio), there are
additional required changes (other than just installing the driver, you
have to tell it to load it before other components (something to do with
the CriticalDeviceDatabse
-----Original Message-----
From: Itamar Heim [mailto:iheim@redhat.com]
Sent: Monday, November 30, 2009 2:33 PM
To: 'Yuval Kashtan'; 'Yaniv Kaul'
Subject: FW: Attempts to install a Windows driver from WinPE
fyi
-----Original Message-----
From: Matthew Booth [mailto:mbooth@redhat.com]
Sent: Monday, November 30, 2009 5:52 AM
To: libguestfs(a)redhat.com
Cc: 'Ayal Baron'; Itamar Heim
Subject: Attempts to install a Windows driver from WinPE
One of the things we would really like to be able to do for V2V is to
install a new driver in a Windows guest. There are a couple of reasons
for this:
* The guest may not be bootable without the driver installed, for
example because the underlying virtual hardware has changed from vmscsi
to virtio.
* If the guest can boot, the alternative is to modify the guest to run
a
script on next boot. This requires making assumptions about supporting
software being installed and working correctly on the guest. Certain
environments, particularly heavily locked-down environments, make this
an unsafe assumption.
The Windows PE environment looks perfect for this task. It gives you a
very lightweight Windows OS which can be customised with additional
tools. It is specifically for doing installations. I spent Friday
trying
to use it to install a driver in a guest. Here's what I tried and why
it
didn't work.
Installing a driver in Windows is 'driven' by a .inf file. From my
(admittedly limited) understanding, this broadly describes:
* The files which need to be installed
* The hardware the driver is compatible with
The files, including the .inf file itself must be copied in to the
correct places. In addition, information from the .inf file must be
written to the registry. It is this last part which causes problems.
From reading documentation, it appears that a driver would normally be
installed using the SetupCopyOEMInf() library call. I wrote a simple
wrapper round this and installed it in the Windows PE image, along with
the VirtIO drivers. I booted into Windows PE and attempted to install
the driver. As you might expect, the drivers were installed into the
Windows PE image rather than the guest. I then tried setting
%systemdrive% and %systemroot% to the guest image. This appears to have
no effect. This is what makes me suspect that the process is primarily
registry driven.
I started looking around for ways of using a different registry. I
discovered the Registry Editor PE plugin to BartPE
(
https://sourceforge.net/projects/regeditpe/) which allows editing the
registry of a guest. Looking at how it does this, it uses reg.exe to
load the guests's hives. I confirmed that you can do this.
Unfortunately
you don't seem to be able to replace the default hives. The new hives
are loaded in a different part of the tree, and are therefore ignored.
This is as far as I've got. Still on my list are:
* Ask on various Windows mailing lists how to do this
* Investigate if the packaged .msi containing the drivers is more
flexible.
* Look for other, possibly lower level, ways of replacing making a
process use a different registry.
Any and all suggestions are gratefully received,
Matt
--
Matthew Booth, RHCA, RHCSS
Red Hat Engineering, Virtualisation Team
M: +44 (0)7977 267231
GPG ID: D33C3490
GPG FPR: 3733 612D 2D05 5458 8A8A 1600 3441 EA19 D33C 3490