Re: [PATCH v7 06/11] pvqspinlock, x86: Allow unfair queue spinlock in a KVM guest

From: Paolo Bonzini
Date: Thu Mar 20 2014 - 18:40:36 EST

Il 20/03/2014 23:29, H. Peter Anvin ha scritto:
> No! Please do what I asked you to do. You are not handling Hyper-V or
> VMWare. Just use X86_FEATURE_HYPERVISOR and it will cover all
> hypervisors that actually follow Intel's guidelines.

And for those that don't, we should turn on X86_FEATURE_HYPERVISOR in
the Linux enumeration code as we do for other features we detect

Yeah, but all the hypervisors we detect right now are fine. Not surprising, since Microsoft won't certify Windows on your hypervisor unless you set the bit, and KVM/Xen/VMware are all certified (Hyper-V does not go through the same certification, but sets it anyway).

I got a second-hand report that VirtualBox doesn't set it---and I haven't verified that yet---but we don't even try to detect vbox right now.

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