Hi Everyone,

We had a requirement to skip all CPU feature validations from libvirt and 
totally rely on Qemu for following reasons.

 * As libvirt always lies behind in term of cpu feature management compare to 
qemu, so we may not be able to use all of the latest support provided by qemu 
till it is updated in libvirt too. For example like if new cpu features are 
added in qemu but not yet updated in libvirt.
 *   Libvirt does not support cpu model versioning as Qemu.
 * Libvirt checks if a features is supported or not based on cpuid, a feature 
supported by host may not be supported by qemu or there can be some features 
which are emulated by Qemu so libvirt level checking does not make sense in 
those cases.
 * Qemu already provide an option 'enforce' to validate if features with which 
vm is started is exactly same as one provided and nothing is silently dropped.

Basically we want another check option like 'qemu-enforce' which will skip all 
feature and cpu model verfications in libvirt and pass 'enforce' option to 
qemu. It will work similar to check 'none' i mean no check to verify if provide 
features are supported by host, also on top of that skip things like 
virCPUValidateFeatures where ever required.

I understand this is specific to just Qemu and libvirt has to take care for 
many other emulator, so wanted to check if something like that makes sense as 
it will be very useful for Qemu atleast. If so we can send a patch.

Thanks

Manish Mishra

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