I am running 2.6.23.1 with kvm built from that tree as a module.  My
system is running Debian/testing on a Tyan board with two dual-core
Opteron 2216 processors; each socket has 4G of RAM.  I have attached the
serial console dump including a bunch of output from SysRq (gzipped,
because it was 300k otherwise).

I have ran multiple passes of memtest, and I can build the kernel with
-j8, but when I run kvm the host freezes.

A bit about the system:

quark# cat /proc/version
Linux version 2.6.23.1 (root@quark) (gcc version 4.2.1 (Debian 4.2.1-4)) #5 SMP Fri Oct 19 14:10:30 EDT 2007

quark# kvm --help
QEMU PC emulator version 0.9.0, Copyright (c) 2003-2007 Fabrice Bellard

My kvm is started as follows; the guest is a 64bit version of RHEL5
(redhatized 2.6.18 kernel).

kvm -m 512 -vnc quark:12 -k en-us -usbdevice tablet -serial vc -k en-us -boot c -hda rhel5.img -net nic,vlan=0 -net user,vlan=0 -redir tcp:2222::22 -redir tcp:8080::8080 -redir udp:8080::8080

I added --no-acpi with no improvement.
I also tried running with taskset -c 0 with no improvement.

Once the system is booted, I attached using vnc, then I ssh in and ran
'svn update'... and the host machine froze.

The last messages I on my serial console are:

kvm: unhandled rdmsr: 0x417
kvm: unhandled rdmsr: 0xc0000400
kvm: unhandled rdmsr: 0xc0000401
kvm: unhandled rdmsr: 0xc0000402
kvm: unhandled rdmsr: 0xc0000403
kvm: unhandled rdmsr: 0xc0000404
kvm: unhandled rdmsr: 0xc0000405
kvm: unhandled rdmsr: 0xc0000406
kvm: unhandled rdmsr: 0xc0000407

And then freeze.

As this is pretty easy to reproduce, I am quite happy to run any patches
or configurations that people come up with :)

I noticed that linus merged a bunch of KVM changes last week.  I will
try those out next.

Thanks in advance for looking at this.

-Bart

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