panic: Duplicate free of item 0xc37aa200 from zone 0xc103f9a0(Mbuf)

[Dan Nelson]

Got this overnight on a 5.3-STABLE 2005-01-13 kernel:

This GDB was configured as "i386-portbld-freebsd5.3"...
panic: Duplicate free of item 0xc37aa200 from zone 0xc103f9a0(Mbuf)

panic messages:
---
panic: Duplicate free of item 0xc37aa200 from zone 0xc103f9a0(Mbuf)

cpuid = 0
--- trap 0x1, eip = 0, esp = 0xe2561d7c, ebp = 0 ---
boot() called on cpu#0
Uptime: 15h14m6s
Dumping 1023 MB
Compressing
Compressed to 314 MB
Dumpsize = 330268160
Dump starting at 475069440
---
#0  doadump () at pcpu.h:159
	in pcpu.h
doadump () at pcpu.h:159
159	in pcpu.h
#0  doadump () at pcpu.h:159
#1  0xc059c1c6 in boot (howto=260) at ../../../kern/kern_shutdown.c:410
#2  0xc059bc3b in panic (fmt=0xc079a0b3 "Duplicate free of item %p from zone %p(%s)\n") at ../../../kern/kern_shutdown.c:566
#3  0xc06e4b96 in uma_dbg_free (zone=0xc103f9a0, slab=0xc37aafa8, item=0xc37aa200) at ../../../vm/uma_dbg.c:299
#4  0xc06e2ce0 in uma_zfree_arg (zone=0xc103f9a0, item=0xc37aa200, udata=0x0) at ../../../vm/uma_core.c:2257
#5  0xc05d760c in m_freem (mb=0x0) at uma.h:302
#6  0xc05d8d15 in m_defrag (m0=0xc37aa200, how=1) at ../../../kern/uipc_mbuf.c:1124
#7  0xc068d49a in dc_start (ifp=0xc238d000) at ../../../pci/if_dc.c:3337
#8  0xc05bf76d in taskqueue_run (queue=0xc2324900) at ../../../kern/subr_taskqueue.c:191
#9  0xc05854f2 in ithread_loop (arg=0xc227d900) at ../../../kern/kern_intr.c:547
#10 0xc05843f9 in fork_exit (callout=0xc0585310 <ithread_loop>, arg=0x0, frame=0x0) at ../../../kern/kern_fork.c:807
#11 0xc071a3dc in fork_trampoline () at ../../../i386/i386/exception.s:209
(gdb)

-- 
	Dan Nelson
	dnelson at allantgroup.com