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Date: Mon, 10 Sep 2007 17:53:36 +0100
From: Jamie Lokier <jamie@shareable.org>
Subject: Re: [kvm-devel] [Qemu-devel] Re: expose host CPU features to guests
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Paul Brook wrote:
> > > What you really want to do is ask your virtualization module what
> > > features it supports.
> >
> > Yes, that needs to be an additional filter.
> 
> I'd have thought that would be the *only* interesting set for autodetection.

If that means the same as the features which are efficient for the
guest, then I agree.  If there's a difference, I'd have thought you'd
normally want the guest to use only those features which work at
near-native performance, not those which involve a trap and long path
through the virtualisation/emulation, even if they're supported.  No
example comes to mind, but that seems like the principle to go for, to
me.

-- Jamie