[libvirt] Passing -no-kvm-irqchip to KVM/QEMU guests

[Garry Dolley]

On Sun, Sep 13, 2009 at 09:33:01PM -0400, Jim Paris wrote:
> Garry Dolley wrote:
> > Dear libvirt,
> > 
> > Is there a way to tell a KVM/QEMU guest managed by libvirt to start
> > with the "-no-kvm-irqchip" argument?
> > 
> > I have some FreeBSD 7 guests with timing issues, and if I try to
> > start the VMs manually with -no-kvm-irqchip, the timing issues go
> > away (the only known workaround right now).
> > 
> > However, if the guest is managed by libvirt, I have found no way to
> > pass this command line option.
> > 
> > I'm running libvirt 0.6.4 on Ubuntu 9.04
> 
> As a hack, you can point the XML file to a wrapper script instead of
> the KVM binary, where the script would contain e.g.:
> 
>   #!/bin/sh
>   exec /usr/bin/kvm "$@" -no-kvm-irqchip

Hi Jim,

Thanks for this suggestion, it worked like a charm!

Now, while this is still a "hacky" way to solve this problem, would
anyone be interested in seeing a patch that would either:

1) Allow one to append arbitrary command line arguments to the
   emulator, like:

     ...
     <emulator>/usr/bin/kvm<emulator>
     <emulator_args>-no-kvm-irqchip</emulator_args>
     ...

   I don't like the name "emulator_args" much either, but just as an
   example.

2) Have an option in the XML file specifically for
   '-no-kvm-irqchip'; I'm not sure where it would go.  Maybe under
   "<features>", yet it isn't really a feature, more like lack of a
   feature ;)

Suggestions welcome.

I've been waiting to find some itch to scratch where I can
contribute to libvirt code directly (instead of just doc patches),
so this seems to fit the bill.

-- 
Garry Dolley
ARP Networks, Inc. | http://www.arpnetworks.com | (818) 206-0181
Data center, VPS, and IP Transit solutions
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