port-amd64/40159: can't boot with multiple cpus anymore

[martin%duskware.de@localhost]

>Number:         40159
>Category:       port-amd64
>Synopsis:       can't boot with multiple cpus anymore
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    port-amd64-maintainer
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Fri Dec 12 19:10:00 +0000 2008
>Originator:     Martin Husemann
>Release:        NetBSD 5.99.5
>Organization:
The NetBSD Foundation, Inc.
>Environment:
System: NetBSD martins.aprisoft.de 5.99.5 NetBSD 5.99.5 (MARTINS) #26: Fri Dec 
12 19:35:19 CET 2008 
martin%martins.aprisoft.de@localhost:/usr/src/sys/arch/amd64/compile/MARTINS 
amd64
Architecture: x86_64
Machine: amd64
>Description:

Since a few days I can't boot without "-1" flag any more. I'm not sure
exactly when this started, but I also did a BIOS upgrade on this machine
recently - maybe that's when.

When I boot with pc keyboard as console, the machine just will hang and
I can't get into ddb. With serial console, however, I can get to ddb and
*always* get the same result:

db{0}> ps/l
 PID         LID S     FLAGS       STRUCT LWP *               NAME WAIT
 5             1 3         4   ffff80004e28f3e0            rcorder biowait
 2             1 3        84   ffff80004e28f7c0                 sh piperd
 1             1 3        84   ffff80004b2bebc0               init wait
>0            45 3       204   ffff80004e28fba0        vmem_rehash vmem_rehash
              44 3       204   ffff80004e289040           aiodoned aiodoned
              43 3       204   ffff80004e289420            ioflush syncer
[..]
              13 1       205   ffff80004b2af040             idle/1
              12 3       204   ffff80004b2af420             sysmon smtaskq
              11 3       204   ffff80004b2af800           pmfevent pmfevent
              10 3       204   ffff80004b2afbe0            cachegc cachegc
               9 3       204   ffff80004b2ac020              vrele vrele
               8 3       204   ffff80004b2ac400          modunload modunload
               7 3       204   ffff80004b2ac7e0            xcall/0 xcall
           >   6 7       204   ffff80004b2acbc0          softser/0
               5 1       204   ffff80004b2aa000          softclk/0
               4 1       204   ffff80004b2aa3e0          softbio/0
               3 1       204   ffff80004b2aa7c0          softnet/0
               2 7       205   ffff80004b2aaba0             idle/0
               1 3       204   ffffffff8052ce40            swapper schedule

>How-To-Repeat:
try to boot my machine ;-)

>Fix:
n/a