Re: [Libvir] PATCH: Explicit detection of KVM version
On Thu, Sep 20, 2007 at 10:45:03AM +0200, Gerd Hoffmann wrote:
Daniel P. Berrange wrote:
> Before starting any guest, the QEMU driver needs to figure out what version
> of QEMU is in use & thus determine whether it supports particular command
> line flags. We currently do that just by calling /usr/bin/qemu, since all
> the various qemu-system-XXX binaries share the same syntax. The only problem
> is that qemu-kvm does not neccessarily match the version of qemu installed.
> So we detect QEMU version 0.8.2, but KVM is 0.9.0 based. The result is that
> we pass the wrong style VNC argument to KVM & it fails to start. The second
> problem is that even if you only ever want to run KVM guests, you still have
> to have KVM itself installed.
We have the same problem if the domain.xml has
"<emulator>/path/to/qemu-foo</emulator>" specified, which I think
isn't
addressed by this patch ...
Nope it is not addressed. I think maybe instead of detecting once for QEMU
and KVM for the QEMU driver as whole, I'll move the flags into the per-VM
data structure. This will have extra overhead, since for each distinct VM
we'll have todo a test launch of QEMU, but VM creation is not a performance
bottleneck so I don't think its an issue.
Dan.
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