From mboxrd@z Thu Jan  1 00:00:00 1970
From: GaoYi <gaoyi709@gmail.com>
Subject: Re: Can VMX provide real mode support?
Date: Wed, 21 Mar 2012 21:56:27 +0800
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	<4F69DA5E.6010505@siemens.com> <4F69DC3B.3050509@redhat.com>
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Cc: Jan Kiszka <jan.kiszka@siemens.com>,
	"qemu-devel@nongnu.org" <qemu-devel@nongnu.org>, kvm <kvm@vger.kernel.org>
To: Avi Kivity <avi@redhat.com>
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Hi,
   Thanks for your prompt response. So if the CPU supports the real
mode, the KVM can support the real mode guest and there is still work to be
done for CPU without real mode support, namely software emulation?

   Again

=D4=DA 2012=C4=EA3=D4=C221=C8=D5 =CF=C2=CE=E79:48=A3=ACAvi Kivity <avi@redh=
at.com>=D0=B4=B5=C0=A3=BA

> On 03/21/2012 03:40 PM, Jan Kiszka wrote:
> > On 2012-03-21 13:38, GaoYi wrote:
> > > Hi Jan,
> > >
> > >     Since the newest Intel-VT supports the guest OS under the real
> mode, which was already supported in AMD-V, can the VMX in the latest KVM
> support that case?
> >
> > Yes, both with our without that "unrestricted guest" support (as Intel
> > called it), real mode will generally work. Without that CPU feature, I
> > think to recall that there were some limitations for big real mode, not
> > sure.
> >
>
> Yes, big real mode will not work without "unrestricted guest".  There
> was some work to emulate it (module option emulate_invalid_guest_state),
> but it is not complete.
>
> --
> error compiling committee.c: too many arguments to function
>
>

--0015175900426226b404bbc12893
Content-Type: text/html; charset=GB2312
Content-Transfer-Encoding: quoted-printable

<div>Hi,</div>
<div>&nbsp;&nbsp;&nbsp;Thanks for your prompt response. So if the CPU suppo=
rts the real mode,&nbsp;the KVM can support the real mode guest and there i=
s still work to be done for CPU without real mode support, namely software =
emulation?</div>

<div>&nbsp;</div>
<div>&nbsp;&nbsp; Again<br><br></div>
<div class=3D"gmail_quote">=D4=DA 2012=C4=EA3=D4=C221=C8=D5 =CF=C2=CE=E79:4=
8=A3=ACAvi Kivity <span dir=3D"ltr">&lt;<a href=3D"mailto:avi@redhat.com">a=
vi@redhat.com</a>&gt;</span>=D0=B4=B5=C0=A3=BA<br>
<blockquote style=3D"BORDER-LEFT:#ccc 1px solid;MARGIN:0px 0px 0px 0.8ex;PA=
DDING-LEFT:1ex" class=3D"gmail_quote">
<div class=3D"im">On 03/21/2012 03:40 PM, Jan Kiszka wrote:<br>&gt; On 2012=
-03-21 13:38, GaoYi wrote:<br>&gt; &gt; Hi Jan,<br>&gt; &gt;<br>&gt; &gt; &=
nbsp; &nbsp; Since the newest Intel-VT supports the guest OS under the real=
 mode, which was already supported in AMD-V, can the VMX in the latest KVM =
support that case?<br>
&gt;<br>&gt; Yes, both with our without that &quot;unrestricted guest&quot;=
 support (as Intel<br>&gt; called it), real mode will generally work. Witho=
ut that CPU feature, I<br>&gt; think to recall that there were some limitat=
ions for big real mode, not<br>
&gt; sure.<br>&gt;<br><br></div>Yes, big real mode will not work without &q=
uot;unrestricted guest&quot;. &nbsp;There<br>was some work to emulate it (m=
odule option emulate_invalid_guest_state),<br>but it is not complete.<br><s=
pan class=3D"HOEnZb"><font color=3D"#888888"><br>
--<br>error compiling committee.c: too many arguments to function<br><br></=
font></span></blockquote></div><br>

--0015175900426226b404bbc12893--

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	<4F69DA5E.6010505@siemens.com> <4F69DC3B.3050509@redhat.com>
Date: Wed, 21 Mar 2012 21:56:27 +0800
Message-ID: <CABurPedppUNeYRw7qw2dmy+i3qQf-XKfHg-rVKV2pyXNZ9CPug@mail.gmail.com>
From: GaoYi <gaoyi709@gmail.com>
Content-Type: multipart/alternative; boundary=0015175900426226b404bbc12893
Subject: Re: [Qemu-devel] Can VMX provide real mode support?
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To: Avi Kivity <avi@redhat.com>
Cc: Jan Kiszka <jan.kiszka@siemens.com>, "qemu-devel@nongnu.org" <qemu-devel@nongnu.org>, kvm <kvm@vger.kernel.org>

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Hi,
   Thanks for your prompt response. So if the CPU supports the real
mode, the KVM can support the real mode guest and there is still work to be
done for CPU without real mode support, namely software emulation?

   Again

=D4=DA 2012=C4=EA3=D4=C221=C8=D5 =CF=C2=CE=E79:48=A3=ACAvi Kivity <avi@redh=
at.com>=D0=B4=B5=C0=A3=BA

> On 03/21/2012 03:40 PM, Jan Kiszka wrote:
> > On 2012-03-21 13:38, GaoYi wrote:
> > > Hi Jan,
> > >
> > >     Since the newest Intel-VT supports the guest OS under the real
> mode, which was already supported in AMD-V, can the VMX in the latest KVM
> support that case?
> >
> > Yes, both with our without that "unrestricted guest" support (as Intel
> > called it), real mode will generally work. Without that CPU feature, I
> > think to recall that there were some limitations for big real mode, not
> > sure.
> >
>
> Yes, big real mode will not work without "unrestricted guest".  There
> was some work to emulate it (module option emulate_invalid_guest_state),
> but it is not complete.
>
> --
> error compiling committee.c: too many arguments to function
>
>

--0015175900426226b404bbc12893
Content-Type: text/html; charset=GB2312
Content-Transfer-Encoding: quoted-printable

<div>Hi,</div>
<div>&nbsp;&nbsp;&nbsp;Thanks for your prompt response. So if the CPU suppo=
rts the real mode,&nbsp;the KVM can support the real mode guest and there i=
s still work to be done for CPU without real mode support, namely software =
emulation?</div>

<div>&nbsp;</div>
<div>&nbsp;&nbsp; Again<br><br></div>
<div class=3D"gmail_quote">=D4=DA 2012=C4=EA3=D4=C221=C8=D5 =CF=C2=CE=E79:4=
8=A3=ACAvi Kivity <span dir=3D"ltr">&lt;<a href=3D"mailto:avi@redhat.com">a=
vi@redhat.com</a>&gt;</span>=D0=B4=B5=C0=A3=BA<br>
<blockquote style=3D"BORDER-LEFT:#ccc 1px solid;MARGIN:0px 0px 0px 0.8ex;PA=
DDING-LEFT:1ex" class=3D"gmail_quote">
<div class=3D"im">On 03/21/2012 03:40 PM, Jan Kiszka wrote:<br>&gt; On 2012=
-03-21 13:38, GaoYi wrote:<br>&gt; &gt; Hi Jan,<br>&gt; &gt;<br>&gt; &gt; &=
nbsp; &nbsp; Since the newest Intel-VT supports the guest OS under the real=
 mode, which was already supported in AMD-V, can the VMX in the latest KVM =
support that case?<br>
&gt;<br>&gt; Yes, both with our without that &quot;unrestricted guest&quot;=
 support (as Intel<br>&gt; called it), real mode will generally work. Witho=
ut that CPU feature, I<br>&gt; think to recall that there were some limitat=
ions for big real mode, not<br>
&gt; sure.<br>&gt;<br><br></div>Yes, big real mode will not work without &q=
uot;unrestricted guest&quot;. &nbsp;There<br>was some work to emulate it (m=
odule option emulate_invalid_guest_state),<br>but it is not complete.<br><s=
pan class=3D"HOEnZb"><font color=3D"#888888"><br>
--<br>error compiling committee.c: too many arguments to function<br><br></=
font></span></blockquote></div><br>

--0015175900426226b404bbc12893--