Re: [Qemu-devel] BSOD when using Hyper-V extensions with Win2k8R2 guests

[Michael Roth]

On Thu, Mar 15, 2012 at 10:26:00PM +0100, Paolo Bonzini wrote:
> Il 15/03/2012 20:14, Michael Roth ha scritto:
> > 
> > Unfortunately the BSOD is too early to get a kernel dump, but here are
> > the error params in case that's useful:
> > 
> > 0xFC0000096, 0xF800027F6200, 0x0, 0x0
> > 
> > Let me know if you need any other details.
> 
> You can use the Windows Boot Debugger.  (Disclaimer: I only used it
> once).  Enable it with "bcdedit /bootdebug {current} ON".
> 
> To use it, you need two Windows VMs (the one that fails and one with
> WinDbg installed).  It is the same as doing normal kernel debugging
> except that the debuggee will hang waiting for a connection even before
> showing the boot loader prompt.  You need to connect the serial consoles
> of the VMs; I usually use socat like
> 
> socat "PIPE:$tty1,unlink-close=0,noctty=1" \
>       "PIPE:$tty2,unlink-close=0,noctty=1
> 
> with the tty names taken from libvirt's XML.  It probably works with
> Unix sockets too but I never tried.

Nice. I knew it was possible but never tried setting it up before. Really
useful to know, thanks!

> 
> From WinDbg you should be able to get a backtrace.  If you never used
> WinDbg, remember to set it up for downloading symbols:
> http://support.microsoft.com/kb/311503
> 
> HTH,
> 
> Paolo
>