From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paolo Bonzini <pbonzini@redhat.com>
Subject: Re: Should KVM_GUEST stop depending on PARAVIRT?
Date: Mon, 27 Jul 2015 20:30:13 +0200
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Cc: KVM list <kvm@vger.kernel.org>
To: Andy Lutomirski <luto@amacapital.net>
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On 27/07/2015 19:51, Andy Lutomirski wrote:
> > > I think I'm missing something.  Does KVM_GUEST hook read_msr and
> > > write_msr?  I don't see it.
> >
> > PARAVIRT does, and it's the main reason why you'd want PARAVIRT for a
> > KVM guest.
>
> Still confused.  On a KVM guest (with PARAVIRT=y), doesn't read_msr do
> exactly the same thing it does on native, albeit with more indirection
> and patching involved?

With PARAVIRT=y it never #GPs:

        .read_msr = native_read_msr_safe,
        .write_msr = native_write_msr_safe,

I don't remember if it's this way on bare-metal too.

Paolo