[Qemu-devel] Kqemu on x86_64 host with x86_64 guest

[Qemu-devel] Kqemu on x86_64 host with x86_64 guest

[Alexander Sennhauser]

Hey there,

Just wanted to check if there is any progress with a x86_64 guest on a
x86_64 host when the kernel module kqemu is enabled. As long the module
is disabled the system boots fine.

Setting: Gentoo x86_64 box as host, guest is a Debian AMD64

Execution: /usr/local/bin/qemu-system-x86_64 -kernel-kqemu -localtime
-net user -net nic,vlan=0,model=rtl8139,macaddr=52:54:00:00:EE:01

The qemu crashes with the following output:

RAX=0000000000000022 RBX=0000000000000022 RCX=00000000000000fa
RDX=ffff810007e31fd8
RSI=0000000000000100 RDI=ffff810007cad040 RBP=ffffffff80524100
RSP=ffffffff804c0f60
R8 =0000000000000003 R9 =0000000000000004 R10=0000000000000046
R11=0000000000010246
R12=000000000000000a R13=0000000000000000 R14=ffff810007cad040
R15=0000000000000004
RIP=ffffffff80210376 RFL=00010202 [-------] CPL=3 II=0 A20=1 SMM=0 HLT=0
ES =0000 0000000000000000 00000000 00000000
CS =0010 0000000000000000 ffffffff 00affa00
SS =0000 0000000000000000 ffffffff 00cff200
DS =0000 0000000000000000 00000000 00000000
FS =0000 0000000000000000 00000000 00000000
GS =0000 0000000000000000 00000000 00000000
LDT=0000 0000000000000000 00000000 00008000
TR =0040 ffff810001003000 0000206f 00008900
GDT=     ffffffff80532000 00000080
IDT=     ffffffff804c7000 00000fff
CR0=8005003b CR2=00002ab037600a80 CR3=000000000742d000 CR4=000006e0
Unsupported return value: 0xffffffff

Re: [Qemu-devel] Kqemu on x86_64 host with x86_64 guest

[Bruno Cornec]

On Thu, Oct 11, 2007 at 06:27:28PM -0700, Alexander Sennhauser wrote:
> Just wanted to check if there is any progress with a x86_64 guest on a
> x86_64 host when the kernel module kqemu is enabled. As long the module
> is disabled the system boots fine.
> 
> Setting: Gentoo x86_64 box as host, guest is a Debian AMD64

I Can say the same of Mandriva 2007.1 as host, and SuSE 10.3,Debian 4.0,
RHEL 5 ... as guests.

> Unsupported return value: 0xffffffff

Exactly the same.

Bruno.
-- 
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Re: [Qemu-devel] Kqemu on x86_64 host with x86_64 guest

[Bruno Cornec]

On Fri, Oct 12, 2007 at 08:04:16AM +0200, Bruno Cornec wrote:
> I Can say the same of Mandriva 2007.1 as host, and SuSE 10.3,Debian 4.0,
> RHEL 5 ... as guests.
> 
> > Unsupported return value: 0xffffffff
> 
> Exactly the same.

However, mandriva 2008.0 x86_64 doesn't exhibit this error on the same
host.

Bruno.
-- 
Des infos sur la musique ancienne  -- http://www.musique-ancienne.org
Des infos sur les logiciels libres -- http://www.HyPer-Linux.org
Home, sweet musical Home -- Lover of Andromède, Béatrice, Early Music, 
Josquin, Linux, Mélisande, Recorder, and Ségolène (not in that order)

Re: [Qemu-devel] Kqemu on x86_64 host with x86_64 guest

[Bruno Cornec]

On Sat, Oct 13, 2007 at 01:53:37PM +0200, Bruno Cornec wrote:
> However, mandriva 2008.0 x86_64 doesn't exhibit this error on the same
> host.

I stand corrected. It also crashed but later during the install process,
where the other were at the start. Back to -no-kqemu.

Bruno.
-- 
Des infos sur la musique ancienne  -- http://www.musique-ancienne.org
Des infos sur les logiciels libres -- http://www.HyPer-Linux.org
Home, sweet musical Home -- Lover of Andromède, Béatrice, Early Music, 
Josquin, Linux, Mélisande, Recorder, and Ségolène (not in that order)

Re: [Qemu-devel] Kqemu on x86_64 host with x86_64 guest

[Werner Dittmann]

Bruno Cornec wrote:
> On Sat, Oct 13, 2007 at 01:53:37PM +0200, Bruno Cornec wrote:
>> However, mandriva 2008.0 x86_64 doesn't exhibit this error on the same
>> host.
> 
> I stand corrected. It also crashed but later during the install process,
> where the other were at the start. Back to -no-kqemu.
> 
> Bruno.
Even when using -no-kqemu it somehow fails/hangs during setup of Grub
when I try to install a openSuse 10.2 or 10.3 . These problems are know
for quite some time - but no solution yet.

Werner

Re: [Qemu-devel] Kqemu on x86_64 host with x86_64 guest

[Bruno Cornec]

On Sat, Oct 13, 2007 at 04:24:45PM +0200, Werner Dittmann wrote:
> Even when using -no-kqemu it somehow fails/hangs during setup of Grub
> when I try to install a openSuse 10.2 or 10.3 . These problems are know
> for quite some time - but no solution yet.

Agreed, but is it only linked to qemu for that grub problem or to grub,
as changing to lilo for x86_64 VMs solves generally the issue.

Bruno.
-- 
Des infos sur la musique ancienne  -- http://www.musique-ancienne.org
Des infos sur les logiciels libres -- http://www.HyPer-Linux.org
Home, sweet musical Home -- Lover of Andromède, Béatrice, Early Music, 
Josquin, Linux, Mélisande, Recorder, and Ségolène (not in that order)

Re: [Qemu-devel] Kqemu on x86_64 host with x86_64 guest

[Julian Seward]

On Saturday 13 October 2007 16:24, Werner Dittmann wrote:
> Bruno Cornec wrote:
> > On Sat, Oct 13, 2007 at 01:53:37PM +0200, Bruno Cornec wrote:
> >> However, mandriva 2008.0 x86_64 doesn't exhibit this error on the same
> >> host.
> >
> > I stand corrected. It also crashed but later during the install process,
> > where the other were at the start. Back to -no-kqemu.
> >
> > Bruno.
>
> Even when using -no-kqemu it somehow fails/hangs during setup of Grub
> when I try to install a openSuse 10.2 or 10.3 . These problems are know
> for quite some time - but no solution yet.

Yes.  I also observed that with openSUSE 10.{1,2,3}.  After some
experimentation I successfully installed 10.1 by asking the installer
to use LILO instead of Grub.  However, even then, some user space
code does not work properly - running the YaST online update inside the
successfully-installed 10.1 fails.

I wondered if there is some problem in the x86_64 instruction set emulation.
I ran some tests from Valgrind, and it appears that some FP->int conversion
instructions do not take care of the rounding mode.  I did not detect
any other errors.  See
http://lists.gnu.org/archive/html/qemu-devel/2007-10/msg00233.html

I tried to build x86_64-softmmu using softfloat.c rather than
softfloat-native.c since it looks like softfloat.c emulates these
corner cases (rounding mode, etc) more completely.  So far I got 
a lot of compilation errors and did not make much progress.  I get
the impression x86_64-softmmu and i386-softmmu are intended only to
be built with softfloat-native.c.

It might be worth installing SuSE 10.1 and finding some small program
which fails to work properly.  Then we might have a hope of determining
what the problem is.

J