>Number:         34024
>Category:       kern
>Synopsis:       panic: kernel diagnostic assertion "pg == NULL || pg->uobject == uobj" failed
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Mon Jul 17 21:15:00 +0000 2006
>Originator:     Florian Franzmann
>Release:        3.0
>Organization:
>Environment:
NetBSD chimaera.hawo.stw.uni-erlangen.de 3.0_STABLE NetBSD 3.0_STABLE (CHIMAERA-
acpi-DEBUG) #1: Mon Jul 17 15:27:38 CEST 2006  root@chimaera.hawo.stw.uni-erlang
en.de:/usr/obj/sys/arch/i386/compile.i386/CHIMAERA-acpi-DEBUG i386
>Description:
Kernel panic after hours of running mencoder. Screen photos of the crash are available at http://www.hawo.stw.uni-erlangen.de/~siflfran/netbsd/

Trace looks like this:
db> trace
cpu_Debugger(c04479b3,cb1e0c38,cb1e0c4c,c034090b,0) at netbsd:cpu_Debugger+0x4
panic(c047b2a0,c0431750,c0466040,c0465ea0,4b7) at netbsd:panic+0x12e
__assert(c0431750,c0465ea0,4b7,c0466040,c0f680d0) at netbsd:__assert+0x2e
genfs_putpages(cb1e0de4,c0f8c200,cb1e0dfc,3,c0419340) at netbsd:genfs_putpages+0
x7aa
VOP_PUTPAGES(cbc499e4,0,0,0,0) at netbsd:VOP_PUTPAGES+0x42
ffs_full_fsync(cb1e0f14,2ef51,537363e0,0,0) at netbsd:ffs_full_fsync+0x326
ffs_fsync(cb1e0f14,cbc499e4,10012,c0298716,c0418b80) at netbsd:ffs_fsync+0x4f
VOP_FSYNC(cbc499e4,ca860000,8,0,0) at netbsd:VOP_FSYNC+0x4e
sched_sync(ca86b7bc,55b000,563000,0,c0100321) at netbsd:sched_sync+0x1ff
db> trace
cpu_Debugger(c04479b3,cb1e0c38,cb1e0c4c,c034090b,0) at netbsd:cpu_Debugger+0x4
panic(c047b2a0,c0431750,c0466040,c0465ea0,4b7) at netbsd:panic+0x12e
__assert(c0431750,c0465ea0,4b7,c0466040,c0f680d0) at netbsd:__assert+0x2e
genfs_putpages(cb1e0de4,c0f8c200,cb1e0dfc,3,c0419340) at netbsd:genfs_putpages+0
x7aa
VOP_PUTPAGES(cbc499e4,0,0,0,0) at netbsd:VOP_PUTPAGES+0x42
ffs_full_fsync(cb1e0f14,2ef51,537363e0,0,0) at netbsd:ffs_full_fsync+0x326
ffs_fsync(cb1e0f14,cbc499e4,10012,c0298716,c0418b80) at netbsd:ffs_fsync+0x4f
VOP_FSYNC(cbc499e4,ca860000,8,0,0) at netbsd:VOP_FSYNC+0x4e
sched_sync(ca86b7bc,55b000,563000,0,c0100321) at netbsd:sched_sync+0x1ff

db> show registers
ds          0x10
es          0x10
fs          0x30
gs          0x10
edi         0xc047b2a0  copyright+0x4a160
esi         0x100
ebp         0xcb1e0bfc
ebx         0xcb1e0c38
edx         0x1
ecx         0x1
eax         0x2691
eip         0xc0336bf4  cpu_Debugger+0x4
cs          0x8
eflags      0x202
esp         0xcb1e0bfc
ss          0x10
netbsd:cpu_Debugger+0x4:        leave

The crash is reproducible. If you need more information please let me know and I will provide them.
>How-To-Repeat:
Run mencoder for several hours.
>Fix:
unknown