kern/42377: netbsd-5 i386 system hangs on file access after changes of around 11/13

[htodd%twofifty.com@localhost]

>Number:         42377
>Category:       kern
>Synopsis:       netbsd-5 i386 system hangs on file access after changes of 
>around 11/13
>Confidential:   no
>Severity:       critical
>Priority:       high
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Wed Nov 25 15:00:01 +0000 2009
>Originator:     H. Todd Fujinaka
>Release:        NetBSD 5.0_STABLE
>Organization:
None
>Environment:
        
        
System: NetBSD kerry.i8u.org 5.0_STABLE NetBSD 5.0_STABLE (KERRY) #1191: Mon 
Nov 23 09:44:39 PST 2009 
htodd%kerry.i8u.org@localhost:/home/obj/sys/arch/i386/compile.i386/KERRY i386
Architecture: i386
Machine: i386
>Description:
My system now hangs during builds of "world" and also on reboot. Similar 
problems are experienced in amd64-current. On reboot the system seems to "hang" 
on unmounting disks. Debugger information (screenshots of the debugger) is 
located at http://www.i8u.org/~htodd/logpix.tar.bz2.

wd0 at atabus2 drive 0: <WDC WD2500KS-00MJB0>
wd0: drive supports 16-sector PIO transfers, LBA48 addressing
wd0: 232 GB, 484521 cyl, 16 head, 63 sec, 512 bytes/sect x 488397168 sectors
wd0: 32-bit data port
wd0: drive supports PIO mode 4, DMA mode 2, Ultra-DMA mode 6 (Ultra/133)
wd0(piixide1:0:0): using PIO mode 4, Ultra-DMA mode 6 (Ultra/133) (using DMA)

# /dev/rwd0d:
type: unknown
disk: NetBSD
label: 
flags:
bytes/sector: 512
sectors/track: 63
tracks/cylinder: 16
sectors/cylinder: 1008
cylinders: 484521
total sectors: 488397168
rpm: 3600
interleave: 1
trackskew: 0
cylinderskew: 0
headswitch: 0           # microseconds
track-to-track seek: 0  # microseconds
drivedata: 0 

16 partitions:
#        size    offset     fstype [fsize bsize cpg/sgs]
 a:   1024128        63     4.2BSD   1024  8192     0  # (Cyl.      0*-   1016*)
 b:   8192016   1024191       swap                     # (Cyl.   1016*-   9143*)
 c: 488397105        63     unused      0     0        # (Cyl.      0*- 484520)
 d: 488397168         0     unused      0     0        # (Cyl.      0 - 484520)
 e:  12288528   9216207     4.2BSD   2048 16384     0  # (Cyl.   9143*-  21334*)
 f:   6144768  21504735     4.2BSD   2048 16384     0  # (Cyl.  21334*-  27430*)
 g: 460747665  27649503     4.2BSD   2048 16384     0  # (Cyl.  27430*- 484520)


        
>How-To-Repeat:
Just start a build, have it hang, then try to reboot.
        
>Fix:
I'll start reveting things 
        

>Unformatted: