I've been having no luck trying to create a new OpenBSD virtual machine under Xen. It was panicing when trying to bring up the xnf0 interface, but the panic went in a loop and spewed tons of repeated messages preventing me from seeing the initial ones on the limited VNC screen.
So I finally found all the magic to switch the installer to a serial
port and connect to it via the Xen console PTY. I'll show the config
below.
Here's the log right from the point where I switch the boot loader to
com0 and connect to the serial console via Xen:
# xl console -t serial puffer
cannot open hd0a:/etc/random.seed: No such file or directory
booting hd0a:/7.9/amd64/bsd.rd: 4264850+1827840+3892024+0+720896
[109+484968+336166]=0xb00b80
entry point at 0xffffffff81001000
Copyright (c) 1982, 1986, 1989, 1991, 1993
The Regents of the University of California. All rights reserved.
Copyright (c) 1995-2026 OpenBSD. All rights reserved. https://www.OpenBSD.org
OpenBSD 7.9 (RAMDISK_CD) #396: Wed May 6 13:25:05 MDT 2026
[email protected]:/usr/src/sys/arch/amd64/compile/RAMDISK_CD
real mem = 1023406080 (975MB)
avail mem = 986275840 (940MB)
random: good seed from bootblocks
mainbus0 at root
bios0 at mainbus0: SMBIOS rev. 2.4 @ 0xfc100000 (11 entries)
bios0: vendor Xen version "4.13.4nb0" date 04/11/2022
bios0: Xen HVM domU
acpi0 at bios0: ACPI 4.0
acpi0: tables DSDT FACP APIC HPET WAET SSDT SSDT
acpitimer0 at acpi0: 3579545 Hz, 32 bits
acpimadt0 at acpi0 addr 0xfee00000: PC-AT compat
ioapic0 at mainbus0: apid 1 pa 0xfec00000, version 11, 48 pins, remapped
cpu0 at mainbus0: apid 0 (boot processor)
cpu0: Intel(R) Xeon(R) CPU E5440 @ 2.83GHz, 834.02 MHz, 06-17-06
cpu0: cpuid 1
edx=1fc9fbff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,CFLUSH,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT>
ecx=80082201<SSE3,SSSE3,CX16,SSE4.1,HV>
cpu0: cpuid a vers=2, gp=2, gpwidth=40, ff=3, ffwidth=40
cpu0: cpuid 80000001 edx=20100800<NXE,LONG> ecx=1<LAHF>
cpu0: MELTDOWN
cpu0: 32KB 64b/line 8-way D-cache, 32KB 64b/line 8-way I-cache, 6MB 64b/line
24-way L2 cache
cpu0: apic clock running at 100MHz
acpihpet0 at acpi0: 62500000 Hz
acpiprt0 at acpi0: bus 0 (PCI0)
acpipci0 at acpi0 PCI0
acpicmos0 at acpi0
"PNP0F13" at acpi0 not configured
"PNP0303" at acpi0 not configured
com0 at acpi0 UAR1 addr 0x3f8/0x8 irq 4: ns16550a, 16 byte fifo
com0: console
acpicpu at acpi0 not configured
pvbus0 at mainbus0: Xen 4.13
xen0 at pvbus0: features 0x2705, 64 grant table frames, event channel 1
xbf0 at xen0 backend 0 channel 5: disk
scsibus0 at xbf0: 1 targets
sd0 at scsibus0 targ 0 lun 0: <Xen, phy xvda 51712, 0000>
sd0: 40960MB, 512 bytes/sector, 83886080 sectors
xbf1 at xen0 backend 0 channel 6: disk
scsibus1 at xbf1: 1 targets
sd1 at scsibus1 targ 0 lun 0: <Xen, phy hdc 5632, 0000>
sd1: 801MB, 512 bytes/sector, 1640448 sectors
"vkbd" at xen0: device/vkbd/0 not configured
xnf0 at xen0 backend 0 channel 7: address 00:16:3e:53:b6:c4
pci0 at mainbus0 bus 0
pchb0 at pci0 dev 0 function 0 "Intel 82441FX" rev 0x02
"Intel 82371SB ISA" rev 0x00 at pci0 dev 1 function 0 not configured
pciide0 at pci0 dev 1 function 1 "Intel 82371SB IDE" rev 0x00: DMA, channel 0
wired to compatibility, channel 1 wired to compatibility
pciide0: channel 0 disabled (no drives)
pciide0: channel 1 disabled (no drives)
"Intel 82371AB Power" rev 0x03 at pci0 dev 1 function 3 not configured
xspd0 at pci0 dev 2 function 0 "XenSource Platform Device" rev 0x01
vga1 at pci0 dev 3 function 0 "Cirrus Logic CL-GD5446" rev 0x00
vga1: aperture needed
wsdisplay at vga1 not configured
isa0 at mainbus0
pckbc0 at isa0 port 0x60/5 irq 1 irq 12
pckbd0 at pckbc0 (kbd slot)
wskbd0 at pckbd0 mux 1
softraid0 at root
scsibus2 at softraid0: 256 targets
root on rd0a swap on rd0b dump on rd0b
WARNING: CHECK AND RESET THE DATE!
erase ^?, werase ^W, kill ^U, intr ^C, status ^T
Welcome to the OpenBSD/amd64 7.9 installation program.
(I)nstall, (U)pgrade, (A)utoinstall or (S)hell? s
# ifconfig -a
lo0: flags=2008008<LOOPBACK,MULTICAST,LRO> mtu 32768
llprio 3
groups: lo
xnf0: flags=8802<BROADCAST,SIMPLEX,MULTICAST> mtu 1500
lladdr 00:16:3e:53:b6:c4
llprio 3
media: Ethernet manual
status: unknown
# ifconfig xnf0 up
uvm_fault(0xfffffd803d81b8a0, 0x48, 0, 2) -> e
fatal page fault in supervisor mode
trap type 6 code 2 rip ffffffff81244381 cs 8 rflags 10202 cr2 48 cpl 4 rsp
ffff80001bddffc0
gsbase 0xffffffff8197bff0 kgsbase 0x0
panic: trap type 6, code=2, pc=ffffffff81244381
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write dfatal double fault in
supervisor mode
trap type 13 code 0 rip ffffffff81122b45 cs 8 rflags 10286 cr2 ffff80001bddcfe8
cpl c rsp ffff80001bddcff0
gsbase 0xffffffff8197bff0 kgsbase 0x0
panic: trap type 13, code=0, pc=ffffffff81122b45
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
panic: netlock rwlock 0xffffffff8196cd38: enter write deadlock
Mon Aug 24 10:59:51 2026
main: End of stream
The Xen xl.cfg(5) file is:
===========================================
type = "hvm"
name = "puffer"
memory = 1000
vcpus = 1
vif = [ 'bridge=bridge0' ]
boot = "cd"
disk = [
'format=raw, vdev=xvda, access=rw, target=/dev/mapper/vg0-puffer.0',
'format=raw, vdev=hdc, access=rw,
target=/xentastic/build/images/OpenBSD-install79.img',
]
serial = [ "pty" ]
vnc = 1
vncdisplay = 10
===========================================
I start the VM with:
xl create -V /etc/xen/puffer.conf
I then quickly (the timeout is _way_ too short!!!) hit the ESC key in
the vncviewer window, then type "2" to boot from the CD image, then
quickly hit the space bar at the "boot>" prompt where I then type:
stty com0 115200
set tty com0
I then return to the xterm with the Xen host's command line and connect
to the serial/PTY console as show above (with "xl console").
I also tried using "sysctl ddb.onpanic=1" to get to the kernel debugger,
but it seems DDB is not built into the install CD's kernel.
I'm willing to download custom CD images to try debugging this, but I
don't currently have a build environment suitable for building my own.
--
Greg A. Woods <[email protected]>
Kelowna, BC +1 250 762-7675 RoboHack <[email protected]>
Planix, Inc. <[email protected]> Avoncote Farms <[email protected]>
pgpg9GKvUNamI.pgp
Description: OpenPGP Digital Signature
