-current crashes immediately after boot on AlphaPC 164

[Dave Huang <khym%azeotrope.org@localhost>]

Hi, I just tried updating my AlphaPC 164 from a March 2013 -current to 
December 22 2013, and it looks like it crashes as soon as the kernel 
finishes booting and it's starting to run processes. If needed, I can 
try to narrow down the time period when this started happening. Or if 
anyone wants me to collect more info, let me know.

[ ... ]
root on sd0a dumps on sd0b
root file system type: ffs

CPU 0: fatal kernel trap:

CPU 0    trap entry = 0x2 (memory management fault)
CPU 0    a0         = 0x0
CPU 0    a1         = 0x1
CPU 0    a2         = 0x1
CPU 0    pc         = 0xfffffc000064043c
CPU 0    ra         = 0xfffffc0000640414
CPU 0    pv         = 0xfffffc00005b7398
CPU 0    curlwp     = 0xfffffc000fbead40
CPU 0        pid = 4, comm = sh

panic: trap
Stopped in pid 4.1 (sh) at      netbsd:cpu_Debugger+0x4:        ret     
zero,(ra)
db> t
cpu_Debugger() at netbsd:cpu_Debugger+0x4
db_panic() at netbsd:db_panic+0x118
vpanic() at netbsd:vpanic+0x184
panic() at netbsd:panic+0x54
trap() at netbsd:trap+0x9ec
XentMM() at netbsd:XentMM+0x20
--- memory management fault (from ipl 0) ---
pmap_destroy() at netbsd:pmap_destroy+0xbc
uvmspace_free() at netbsd:uvmspace_free+0xf8
uvm_proc_exit() at netbsd:uvm_proc_exit+0x9c
exit1() at netbsd:exit1+0x218
sys_exit() at netbsd:sys_exit+0x5c
syscall() at netbsd:syscall+0x2b0
XentSys() at netbsd:XentSys+0x5c
--- syscall (1) ---
--- user mode ---

-- 
Name: Dave Huang         |  Mammal, mammal / their names are called /
INet: khym%azeotrope.org@localhost |  they raise a paw / the bat, the cat /
FurryMUCK: Dahan         |  dolphin and dog / koala bear and hog -- TMBG
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