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From: Roman Kagan <rkagan@virtuozzo.com>
Date: Fri, 25 Jan 2019 12:47:41 +0000
Message-ID: <20190125124738.GB30730@rkaganb.sw.ru>
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Subject: Re: [Qemu-devel] [PATCH RFC 4/8] i386/kvm: Implement 'hv-all'
 pass-through mode
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To: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: "qemu-devel@nongnu.org" <qemu-devel@nongnu.org>, Paolo Bonzini <pbonzini@redhat.com>, Richard Henderson <rth@twiddle.net>, Eduardo Habkost <ehabkost@redhat.com>, Marcelo Tosatti <mtosatti@redhat.com>

On Fri, Jan 25, 2019 at 12:41:51PM +0100, Vitaly Kuznetsov wrote:
> In many case we just want to give Windows guests all currently supported
> Hyper-V enlightenments and that's where this new mode may come handy. We
> pass through what was returned by KVM_GET_SUPPORTED_HV_CPUID.

How is the compatibility ensured on migration between kernels reporting
different feature sets?

Roman.