[et-mgmt-tools] virt-manager feature request

[Daniel P. Berrange]

On Sat, Oct 06, 2007 at 02:50:07PM +0200, Farkas Levente wrote:
> hi,
> there are different hypervisor supported by virt-manager and it's not
> possible to add all features of all hypervisor to the gui, what's more
> even for common features missing from the gui. meanwhile these wil be
> implemented it'd be useful to be able to use these feature even for
> those who use virt-manager. so imho it'd be useful if i can define
> additional parameters to the command line argument which is composed by
> virt-manager or libvirt. eg: with kvm as all newer version then kvm-36
> has many bugs the developer always ask what happendes with
> -no-kvm-irqchip? but currently i can't run guests from virt-manager with
> this settings. so it'd be useful if i can define addition command line
> argument to qemu-kvm eg. a simple imput line which is appended to the
> command line would be useful. and all hypervisor can benefit from this
> feature.

The trouble with allowing the defining of arbitrary extra command line
parameters is that this can change the behaviour of QEMU which will impact 
the ability of libvirt to reliably manage the guest process. QEMU is very
sensitive to the order of command line args in some cases & adding extra
args can have unpredictable effects on the way it runs. Furthermore hacks 
like -no-kvm-irqchip are not sustainable / supportable long term - the only 
viable approach is to make KVM itself more reliable. If this means sticking 
on -36 for a while while bugs with the KVM IRQ handling in newer releases 
are ironed out so be it. 

Dan.
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