FFS/UFS2 Kernel Panic in RELENG_5_2

Hi All,
    Was playing around with snapshots when I got the following panic:

panic: lockmgr: locking against myself

The situation was:
    rsync to machine
    snapshot filesystem
    rsync to machine again

The drive it's on is 250GB IDE and the snapshot took about 3 minutes.
No ATA errors were reported.

Full debug info at:

http://clearchain.com/people/benjsc/download/freebsd/20040119/typescript.gz 
(7Kb)
http://clearchain.com/people/benjsc/download/freebsd/20040119/kernel.debug.gz  
(11Mb)
http://clearchain.com/people/benjsc/download/freebsd/20040119/vmcore.2.gz 
(86Mb)

Basics below:

FreeBSD rsync.levels.unisa.edu.au 5.2-RELEASE FreeBSD 5.2-RELEASE #0: 
Mon Jan 19 05:47:07 CST 2004     root_at_rsync.l
evels.unisa.edu.au:/usr/src/sys/i386/compile/GENERIC  i386


(kgdb) bt
#0  doadump () at ../../../kern/kern_shutdown.c:240
#1  0xc0631e5c in boot (howto=260) at ../../../kern/kern_shutdown.c:372
#2  0xc06321ce in panic () at ../../../kern/kern_shutdown.c:550
#3  0xc076e070 in ffs_copyonwrite (devvp=0xc2e7e104, bp=0xc7e45890) at 
../../../ufs/ffs/ffs_snapshot.c:1934
#4  0xc05faeb2 in spec_xstrategy (vp=0xc2e7e104, bp=0xc7e45890) at 
../../../fs/specfs/spec_vnops.c:474
#5  0xc05fafab in spec_specstrategy (ap=0x0) at 
../../../fs/specfs/spec_vnops.c:534
#6  0xc05fa278 in spec_vnoperate (ap=0x0) at 
../../../fs/specfs/spec_vnops.c:122
#7  0xc0788bec in ufs_strategy (ap=0x0) at vnode_if.h:1141
#8  0xc0789938 in ufs_vnoperate (ap=0x0) at 
../../../ufs/ufs/ufs_vnops.c:2793
#9  0xc0674a1d in bwrite (bp=0xc7e45890) at vnode_if.h:1116
#10 0xc06767b2 in vfs_bio_awrite (bp=0xc7e45890) at 
../../../kern/vfs_bio.c:1715
#11 0xc077b50c in ffs_fsync (ap=0xd304f284) at 
../../../ufs/ffs/ffs_vnops.c:268
#12 0xc077a6c4 in ffs_sync (mp=0xc2e14000, waitfor=2, cred=0xc16bc100, 
td=0xc08ef1c0) at vnode_if.h:627
#13 0xc068976e in sync (td=0xc08ef1c0, uap=0x0) at 
../../../kern/vfs_syscalls.c:141
#14 0xc0631a54 in boot (howto=256) at ../../../kern/kern_shutdown.c:281
#15 0xc06321ce in panic () at ../../../kern/kern_shutdown.c:550
#16 0xc06268de in lockmgr (lkp=0xc7dcd45c, flags=34144290, interlkp=0x0, 
td=0xc2e40b40)
    at ../../../kern/kern_lock.c:439
#17 0xc0677bcf in getblk (vp=0xc2e7e104, blkno=196079584, size=16384, 
slpflag=0, slptimeo=0, flags=0)
    at machine/pcpu.h:156
#18 0xc06742f2 in breadn (vp=0xc2e7e104, blkno=0, size=0, rablkno=0x0, 
rabsize=0x0, cnt=0, cred=0x0, bpp=0x0)
    at ../../../kern/vfs_bio.c:700
#19 0xc067429c in bread (vp=0x0, blkno=0, size=0, cred=0x0, bpp=0x0) at 
../../../kern/vfs_bio.c:682
#20 0xc0760b4f in ffs_alloccg (ip=0xc2e2d460, cg=521, bpref=0, 
size=16384) at ../../../ufs/ffs/ffs_alloc.c:1287
#21 0xc07605ef in ffs_hashalloc (ip=0xc2e2d460, cg=521, pref=0, 
size=16384, allocator=0xc0760a60 <ffs_alloccg>)
    at ../../../ufs/ffs/ffs_alloc.c:1165
#22 0xc075e452 in ffs_alloc (ip=0xc2e2d460, lbn=6127491, bpref=48929048, 
size=16384, cred=0xc16bc100,
    bnp=0xd304f5e0) at ../../../ufs/ffs/ffs_alloc.c:157
#23 0xc0765b53 in ffs_balloc_ufs2 (vp=0xc2e7ee38, startoffset=0, 
size=16384, cred=0xc16bc100, flags=0,
    bpp=0xd304f6f0) at ../../../ufs/ffs/ffs_balloc.c:774
#24 0xc076e408 in ffs_copyonwrite (devvp=0xc2e7e104, bp=0xc7e15320) at 
../../../ufs/ffs/ffs_snapshot.c:2029
#25 0xc05faeb2 in spec_xstrategy (vp=0xc2e7e104, bp=0xc7e15320) at 
../../../fs/specfs/spec_vnops.c:474
#26 0xc05fafab in spec_specstrategy (ap=0x0) at 
../../../fs/specfs/spec_vnops.c:534
#27 0xc05fa278 in spec_vnoperate (ap=0x0) at 
../../../fs/specfs/spec_vnops.c:122
#28 0xc06749f4 in bwrite (bp=0xc7e15320) at vnode_if.h:1141
#29 0xc067523c in bawrite (bp=0x0) at ../../../kern/vfs_bio.c:1150
#30 0xc0761a0a in ffs_nodealloccg (ip=0xc3189834, cg=521, ipref=129, 
mode=33152)
    at ../../../ufs/ffs/ffs_alloc.c:1637
#31 0xc0760597 in ffs_hashalloc (ip=0xc3189834, cg=521, pref=0, size=33152,
    allocator=0xc07614b0 <ffs_nodealloccg>) at 
../../../ufs/ffs/ffs_alloc.c:1155
#32 0xc075fcc9 in ffs_valloc (pvp=0xc3508208, mode=33152, 
cred=0xc2f3f680, vpp=0xd304f8dc)
    at ../../../ufs/ffs/ffs_alloc.c:857
#33 0xc078923c in ufs_makeinode (mode=33152, dvp=0xc3508208, 
vpp=0xd304fbf0, cnp=0xd304fc04)

Cheers,
    Benjamin

-- 
3D Research Associate / System Administrator     +61 8 8302 3669
School of Computer and Information Science       Room D1-07, ML Campus
University of South Australia                    Mawson Lakes Blvd.
Benjamin.Close_at_cs.unisa.edu.au                   South Australia, 5095
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