In this post, I provide the latest build of the Windows Paravirtual Block Drivers pulled from the git repository. The most recent change to the source code was made on November 25th 2009 so it’s a little over a month old. I’ll walk you through upgrading your current installation of kvm windows paravirtual block drivers if you already have them installed. If you’re installing these drivers for the first time, you can find the procedure for doing so at another post here. Upgrading is simple and straightforward. Upgrading these drivers is like upgrading any other driver in windows but I decided to outline the procedure below for the benefit of those who have never done it before.

Changelog

Below shows the changelog based on git logs. Just changes relevant to viostor driver are shown.

[VirtIO] Add op to the library enable\disable the interrupts
      Correct clean up during surprise removal. The bug was found during WHQL tests of Windows 2008 R2
      [WIN-GUEST-DRIVERS] Initial support for MSI interrupts and DPC\Interrupt behaviour
      [WIN-GUEST-DRIVERS] viostor driver. Code cleanup. Getting rid of the Registry stuff.
      On SMP guests, reads from the ring might bypass used index reads. This causes guest crashes because host writes to used index to signa
      [WIN-GUEST-DRIVERS] viostor driver. Switch to full-duplex mode.
      [WIN-GUEST-DRIVERS] viostor driver. Complete SRBs at DPC level. Fixing previous commit.
      [WIN-GUEST-DRIVERS] viostor driver. Add support for serial number feature.
      [WIN-GUEST-DRIVERS] Add MSI-X support for viostor driver
      [WIN-GUEST-DRIVERS] Fix clean.bat for viostor to delete *.err files that might be created due to failed compilation.
      [WIN-GUEST-DRIVERS] viostor. Fix broken XP build
      [WIN-GUEST-DRIVERS] Clean up prefast (MS static code analyzer tool) errors.
      [WIN-GUEST-DRIVERS] viostor driver. remove trailing white spaces
      [WIN-GUEST-DRIVERS] viostor driver.Add memory read barrier - synch with fix for Linux guests by Michael S. Tsirkin<mst@redhat.com>
      [WIN-GUEST-DRIVERS] Fix the driver version report through OID. Will fix the warning during MS tests.
      [WIN-GUEST_DRIVERS]     viostor driver. some steps toward better performance on XP.
      [WIN-GUEST_DRIVERS] viostor driver. fix PREfast warnings.
      [WIN-GUEST_DRIVERS] viostor driver. Xp driver performance.
      [WIN-GUEST_DRIVERS]     viostor driver. small fix in startio routine (storport related path).

Upgrading KVM Windows block drivers

Navigate to your hardware drivers by right clicking on your “My Computer” icon and select Properties. Select “Hardware” then “Device Manager”. Navigate to “SCSI and RAID controllers” and select any one of the “Red Hat VirtIO SCSI controller” devices. Right click on the controller and select “Upgrade Driver...”

The hardware wizard update will appear. Select “No, not at this time” to specify the location of the drivers.

Select “Install from a list or specific location”

Navigate to the CDROM iso provided at the end of this post. This driver included are for Windows 2003 and 2008 for both 32 and 64 bit architectures. The example below shows how to select drivers for 32-bit windows 2003.

Select Next to begin Installation.

The installation/upgrade process will begin.

After the installation you’ll see the following windows notifying you that it was successfully completed. Note that it says “The hardware you installed will not work until you restart your computer”. This will only apply if you upgraded the driver for your system disk. If you upgraded a non system disk you will not be prompted to reboot your computer.

To confirm that your driver has been updated you can look at the properties of your block drivers before and after upgrade. You’ll see that the driver version and date has been upaded as shown below.

Below shows my driver date and version before update

Below shows my driver date and version after update.

I haven’t gotten these drivers to work with 32-bit windows xp guest and to be honest haven’t really tried since I mostly use a windows 2003 guest. Give these drivers a try and feel free to post any comments or questions.