From: Paolo Bonzini <pbonzini@redhat.com>
To: Andy Lutomirski <luto@amacapital.net>
Cc: KVM list <kvm@vger.kernel.org>
Subject: Re: Should KVM_GUEST stop depending on PARAVIRT?
Date: Mon, 27 Jul 2015 20:30:13 +0200 [thread overview]
Message-ID: <55B678B5.8040602@redhat.com> (raw)
In-Reply-To: <CALCETrVKzvkQMZOpm4McPoR8fTjPt-b2u=3NgydfLAvPxdr5yg@mail.gmail.com>
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
next prev parent reply other threads:[~2015-07-27 18:30 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-07-24 17:33 Should KVM_GUEST stop depending on PARAVIRT? Andy Lutomirski
2015-07-27 13:59 ` Paolo Bonzini
2015-07-27 15:56 ` Andy Lutomirski
2015-07-27 17:49 ` Paolo Bonzini
2015-07-27 17:51 ` Andy Lutomirski
2015-07-27 18:30 ` Paolo Bonzini [this message]
2015-07-27 18:45 ` Andy Lutomirski
2015-07-27 19:04 ` Arjan van de Ven
2015-07-28 9:57 ` Paolo Bonzini
2015-07-29 0:23 ` Andy Lutomirski
2015-07-29 4:49 ` Venkatesh Srinivas
2015-07-29 8:27 ` Paolo Bonzini
2015-07-29 9:19 ` Peter Zijlstra
2015-07-29 9:24 ` Paolo Bonzini
2015-07-29 9:40 ` Peter Zijlstra
2015-07-29 9:41 ` Paolo Bonzini
2015-07-30 0:14 ` Andy Lutomirski
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