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-- Ben Armstrong, Virtualization Program Manager

Talking about core virtualization at Microsoft (Hyper-V, Virtual PC and Virtual Server).

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Problems with Intelppm.sys and processr.sys under Virtual PC / Virtual Server

Under certain circumstances with a Windows XP / 2003 operating system - intelppm.sys and processr.sys can cause a virtual machine running under Virtual PC / Virtual Server to crash (by default this will cause the Windows guest operating system to reboot automatically - but if you have changed this setting you will see a blue screen).  The reason for this crash is because these drivers are attempting to perform an unsupported operation inside of the virtual machine (like upgrading the physical processors microcode, changing power state on the physical processor).

Today this problem only occurs on Centrino and AMD K8 processors.  Most people see this problem when they move a virtual machine that was created on another type of processor to a computer running one of these types of processors (and then they usually see the problem when they attempt to shutdown their virtual machine for the first time).  Now you may be wondering why you have not heard about this problem more often - and the reason for that is that if these drivers fail once - they are smart enough to not attempt to perform the operation that failed again.

If you are seeing this problem repeatedly you can manually disable these drivers (with no negative side effect) by going to the following location in the registry:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Processor

Or

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Intelppm

And changing the 'Start' value to '4'.

In the mean time we have made some subtle changes to the way our hardware exposes the processor in Virtual Server R2 so that in future products these drivers should never get loaded inside of virtual machines.

Cheers,
Ben

Published Monday, October 24, 2005 9:25 PM by Virtual PC Guy

Comments

# re: Problems with Intelppm.sys and processr.sys under Virtual PC / Virtual Server

this might help mysterious reboots that I get (daily it seems) from my 2003server guest (XP host).

so do we change the host or guest registery?
Tuesday, October 25, 2005 12:34 AM by bobm

# re: Problems with Intelppm.sys and processr.sys under Virtual PC / Virtual Server

Sorry for not being clear there - you make the change in the guest registry.

Cheers,
Ben
Tuesday, October 25, 2005 12:43 AM by Virtual PC Guy

# re: Problems with Intelppm.sys and processr.sys under Virtual PC / Virtual Server

So that's why VirtualPC doesn't work right on my (Centrino) laptop!

Also, rather than wondering around in the registry, you're better off using "SC" command (included with Windows XP/2003), like this:
sc config processor start= disabled
sc config intelppm start= disabled
This is in the guest OS, of course.
Wednesday, October 26, 2005 4:04 AM by Jonathan

# re: Problems with Intelppm.sys and processr.sys under Virtual PC / Virtual Server

Thanx, Ben & Jonathan. We just slammed into this issue with one of our [Avanade's] clients, but it's going the other way from what you described. A W2k3 image created and sysprep-ed on a Centrino notebook tanked when run on a desktop P4 w/ HT... The processor service couldn't be found on the image, but the "sc config intelppm start= disabled" cured it AFTER I copied the image to the P4 BEFORE running sysprep. Thank you!! Note that it didn't work when I disabled intelppm and sysprep-ed on the Centrino and then tried to run it on the PCs...
Thursday, October 27, 2005 12:51 PM by David Reed

# re: Problems with Intelppm.sys and processr.sys under Virtual PC / Virtual Server

Ben,

FYI, I have the problem consistently on my DELL XPS Gen 4 (Intel P4 3.6 GHz, hyperthreading on) running Windows XP Media Center 2005.

Cheers,

Brian
Friday, November 04, 2005 9:28 PM by Brian Randell

# re: Problems with Intelppm.sys and processr.sys under Virtual PC / Virtual Server

Note: I had to use the SC commands at a Safe Mode with Command Prompt because my VPC Instance couldn't even login without blue screening. After applying the two changes in Safe mode everything works fine.
Tuesday, November 15, 2005 1:17 PM by Steele Price
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