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Date: Wed, 8 Nov 2017 18:07:02 -0200
From: Eduardo Habkost <ehabkost@redhat.com>
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Subject: Re: [Qemu-devel] [libvirt] [PATCH 0/7] x86: Rework KVM-defaults
 compat code, enable kvm_pv_unhalt by default
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To: Paolo Bonzini <pbonzini@redhat.com>
Cc: Waiman Long <longman@redhat.com>, Davidlohr Bueso <dave@stgolabs.net>, "Michael S. Tsirkin" <mst@redhat.com>, libvir-list@redhat.com, qemu-devel@nongnu.org, Igor Mammedov <imammedo@redhat.com>

On Tue, Nov 07, 2017 at 12:21:16PM +0100, Paolo Bonzini wrote:
> On 14/10/2017 01:56, Eduardo Habkost wrote:
> > Now, I don't know yet what's the best default for a guest that
> > has CONFIG_PARAVIRT_SPINLOCK when it sees a host that supports
> > kvm_pv_unhalt.  But I'm arguing that it's the guest
> > responsibility to choose what to do when it detects such a host,
> > instead of expecting the host to hide features from the guest.
> > The guest and the guest administrator have more information to
> > choose what's best.
> > 
> > In other words, if exposing kvm_pv_unhalt on CPUID really makes
> > some guests behave poorly, can we fix the guests instead?
> 
> Waiman just did it. :)
> 
> https://marc.info/?l=linux-kernel&m=150972337909996

Thanks for the pointer.  I will resubmit the series for 2.12
after 2.11 is released.

-- 
Eduardo