In principle, could vbox make a VM's CPU appear to be a different type than the actual physical one?
For example, could it provide a more generic cpu (ie. missing Intel or AMD specific features) so that it's easier to transport VMs between heterogeneous hardware?
I was wondering if it would be trivial, or would require BOCHS-like full-on (and slow) CPU emulation.
CPU virtualisation
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Sasquatch
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Re: CPU virtualisation
VB passes the exact same CPU to the VM as the Host is running, only a few features of the CPU are stripped to avoid certain problems.
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NeBlackCat
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Re: CPU virtualisation
I know, hence the question!Sasquatch wrote:VB passes the exact same CPU to the VM as the Host is running, only a few features of the CPU are stripped to avoid certain problems.
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Sasquatch
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Re: CPU virtualisation
Hence my answer, you can't change the type or ID VB sends to the Guest. Only a generic set of instructions are passed on, or a few are left out. One of the other.
Read the Forum Posting Guide before opening a topic.
VirtualBox FAQ: Check this before asking questions.
Online User Manual: A must read if you want to know what we're talking about.
Howto: Install Linux Guest Additions
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VirtualBox FAQ: Check this before asking questions.
Online User Manual: A must read if you want to know what we're talking about.
Howto: Install Linux Guest Additions
Howto: Use Shared Folders on Linux Guest
See the Tutorials and FAQ section at the top of the Forum for more guides.
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NeBlackCat
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Re: CPU virtualisation
I'm not following you. I know you can't (currently). Hence I'm asking "how hard would it be for vbox to have this added?". For example (IIRC) ESX allows you to specify a bitmask that's applied to the value returned by the physical CPU to the CPUID instruction before the target gets it (might require VT-d though, I can't remember).