From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Lacombe <goretux@gmail.com>
Subject: Re: [x86] - technical questions about HV implementation on Intel VT
Date: Wed, 29 Apr 2009 16:50:15 +0200
Message-ID: <200904291650.16079.goretux@gmail.com>
References: <200903241822.11529.goretux@gmail.com> <49ECBD5D.4080205@redhat.com> <200904211316.06778.goretux@gmail.com>
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Cc: kvm@vger.kernel.org
To: Avi Kivity <avi@redhat.com>
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Hi,

Le mardi 21 avril 2009 13:16:06 Eric Lacombe, vous avez =E9crit :
> Le lundi 20 avril 2009 20:22:21 Avi Kivity, vous avez =E9crit :
> > Eric Lacombe wrote:

[...]

> > echo and pwd are part of bash, so they are probably in memory.  I g=
uess
> > once you go to disk things fail.
> >
> > Try to boot the entire OS from initramfs (and keep it there).
>
> I will try this but maybe what follows say that the problem is elsewh=
ere.

I setup a minimal initramfs with busybox and my module inside.
The init script in the initramfs only mount /proc /sys, populate /dev (=
busybox=20
mdev), then execute the busybox shell.

Then when I insmod'ed my module, I had to cope with an exit reason at t=
he very=20
first entry (through vmlaunch) to the VM.
This was because of the host and guest fs_selector VMCS fields, whose T=
I and=20
RPL bits were not 0.

After fixing that (setting TI and RPL bits to 0, instead of using direc=
tly fs=20
and gs values), the vmlaunch succeed, and I got quite the same behaviou=
r as=20
when the system boots with the rootfs pointing to the hard disk, i.e. t=
he=20
system works for "echo", "pwd", ... but freezes after a ls for example.

I say "quite", as I sometime got a freeze after a "echo something".
So the problem is definitely not a problem with files on the hard disk.=
=2E.

Do you have some new hints on what could go wrong?
And what could I try to resolve this problem?

I really need to resolve that thing, and all assistance is more than gr=
eatly=20
welcome ;)

Thanks in advance for your response and the time you have already spent=
 to=20
help me.

	Eric Lacombe