From mboxrd@z Thu Jan  1 00:00:00 1970
From: =?ISO-8859-1?Q?Andr=E9_Weidemann?= <Andre.Weidemann@web.de>
Subject: Re: Windows7 crashes inside the VM when starting a certain program
Date: Tue, 26 Jul 2011 07:29:04 +0200
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On 07.07.2011 07:26, Andr=E9 Weidemann wrote:
> Hi,
> I am running Windows7 x64 in a VM which crashes after starting a cert=
ain
> game. Actually there are two games both from the same company, that m=
ake
> the VM crash after starting them.
> Windows crashes right after starting the game. With the 1st game the
> screen goes black as usual and the cursor keeps spinning for 3-5 seco=
nds
> until Windows crashes. With the second game I get to 3D the login
> screen. The game then crashes after logging in.
> Windows displays this error message on the first crash:
> http://pastebin.com/kMzk9Jif
> Windows then finishes writing the crash dump and restarts.
> I can reproduce Windows crashing every time I start the game while th=
e
> VM keeps running without any problems.
> When Windows reboots after the first crash and the game is started
> again, the message on the following blue screen changes slightly and
> stays the same(except for the addresses) for every following crash:
> http://pastebin.com/jVtBc4ZH
>
> I first thought that this might be related to a certain feature in 3D
> acceleration being used, but Futuremark 3DMark Vantage or 3DMark 11 r=
un
> without any problems. They run a bit choppy on some occasions, but do
> that without crashing Windows7 or the VM.
>
> How can I proceed to investigate what is going wrong?

I did some testing and found out that Windows7 does not crash anymore=20
when changing "-cpu host" to "-cpu Nehalem". After doing so, the "only"=
=20
thing crashing, is the application itself.
Why is that? What is different between the "real" CPU and the one=20
provided by qemu-kvm? How can "-cpu host" cause Windows7 to crash, whil=
e=20
"-cpu Nehalem" "only" crashes the application.

I then had WinDbg attach to the process in question. When the game=20
crashes the debugger reports an Assertion Failure. This seems so happen=
=20
as soon as the game accesses the network through a certain DLL.
To exclude the emulated e1000 hardware as the cause, I  removed it from=
=20
the VM and passed an Intel network card 82574L to it using these lines:

-device pci-assign,host=3D04:00.0,id=3D82574L,addr=3D0x10 \
-net none \

The network card works under Windows7, but the problem of the crashing=20
game remains.

Any ideas on how to track the problem are greatly appreciated.


Regards
  Andr=E9