init getting SIGILL on recent XEN3PAE_DOMU

["Brent Verner" <brent%netavail.com@localhost>]

Hi,

  Sometime after Apr 20, XEN3PAE_DOMU kernels have been unable to boot.
due to init getting a SIGILL and restarting ad infinitum.  I tried to
poke at this
with ddb, but I couldn't figure out how to figure out _what_ was causing the
SIGILL.  Below are the boot messages and a trace from ddb.

I'm more than happy to help diagnose this, but I would need some
assistance/instruction to get any further.

cheers!
  Brent


Loaded initial symtab at 0xc051bb34, strtab at 0xc055452c, # entries 13516
Started domain test
                   Copyright (c) 1996, 1997, 1998, 1999, 2000, 2001,
2002, 2003, 2004, 2005,
    2006, 2007, 2008
    The NetBSD Foundation, Inc.  All rights reserved.
Copyright (c) 1982, 1986, 1989, 1991, 1993
    The Regents of the University of California.  All rights reserved.

NetBSD 4.99.62 (XEN3PAE_DOMU) #4: Wed Apr 30 08:40:19 EDT 2008
        
brent%nbsd.build.netavail.com@localhost:/usr/build/obj/sys/arch/i386/compile/XEN3PAE_DOMU
total memory = 65536 KB
avail memory = 57804 KB
mainbus0 (root)
hypervisor0 at mainbus0
vcpu0 at hypervisor0: (uniprocessor)
vcpu0: AMD Athlon XP 2600+ (686-class), 1916.45 MHz, id 0x6a0
vcpu0: "AMD Athlon(TM) XP 2600+"
vcpu0: 8 page colors
xenbus0 at hypervisor0: Xen Virtual Bus Interface
xencons0 at hypervisor0: Xen Virtual Console Driver
xencons0: using event channel 2
npx0 at hypervisor0: using exception 16
xenbus0: using event channel 1
xbd0 at xenbus0 id 2048: Xen Virtual Block Device Interface
xennet0 at xenbus0 id 0: Xen Virtual Network Interface
xennet0: MAC address 3e:06:7a:f9:e5:03
unknown type console at xenbus0 id 0 not configured
xbd0: 512 MB, 512 bytes/sect x 1048576 sectors
raidattach: Asked for 8 units
Kernelized RAIDframe activated
Searching for RAID components...
boot device: xbd0
root on xbd0a dumps on xbd0b
dump_misc_init: max_paddr = 0x4000000
mountroot: trying lfs...
unknown type console at xenbus0 id 0 not configured
unknown type console at xenbus0 id 0 not configured
mountroot: trying ffs...
root file system type: ffs
init: copying out path `/sbin/init' 11
Process (pid 1) got sig 4
Process (pid 1) got sig 4
[...]
Process (pid 1) got sig 4
Stopped in pid 1.1 (init) at    netbsd:breakpoint+0x4:  popl    %ebp
db> bt
breakpoint(c051b2f4,0,c6125fbc,4,1) at netbsd:breakpoint+0x4
xencons_tty_input(c079def0,c060c004,1,c04f426c,c051b2f4) at
netbsd:xencons_tty_input+0xa6
xencons_handler(c079def0,c613ebbc,0,0,0) at netbsd:xencons_handler+0x5f
DDB lost frame for netbsd:Xresume_xenev6+0x41, trying 0xc6125ff4
Xresume_xenev6() at netbsd:Xresume_xenev6+0x41
--- interrupt ---
--- switch to interrupt stack ---
Xspllower(0,1,0,0,c613ec50) at netbsd:Xspllower+0xe
printf_nolog(c046fce8,1,4,0,c5936074) at netbsd:printf_nolog+0x5f
issignal(c594d900,c5951000,4,c613ecf0,c613ecf0) at netbsd:issignal+0x319
lwp_userret(c594d900,c613ecf0,c0102515,c594d900,c0823000) at
netbsd:lwp_userret+0x130
trap() at netbsd:trap+0x48d
--- trap (number 0) ---
0xbb7f46d0:
db>