Fxp / polling / witness panic

Latest sources with following debugging options set yields the panic below.

makeoptions     DEBUG=-g
options         KTRACE
options         DDB
options         DDB_UNATTENDED
options         ALT_BREAK_TO_DEBUGGER
options         INVARIANTS
options         INVARIANT_SUPPORT
options         WITNESS
options         WITNESS_SKIPSPIN

#0  doadump () at /usr/src/sys/kern/kern_shutdown.c:238
238             dumping++;
(kgdb) bt
#0  doadump () at /usr/src/sys/kern/kern_shutdown.c:238
#1  0xc01d8133 in boot (howto=256) at /usr/src/sys/kern/kern_shutdown.c:370
#2  0xc01d847b in panic () at /usr/src/sys/kern/kern_shutdown.c:543
#3  0xc01fb681 in witness_lock (lock=0xc1526160, flags=8, 
    file=0xc0308197 "/usr/src/sys/dev/fxp/if_fxp.c", line=1465)
    at /usr/src/sys/kern/subr_witness.c:722
#4  0xc01cec71 in _mtx_lock_flags (m=0xc151c3fc, opts=0, 
    file=0xc038be2c "`aRÁ\227\2010ÀÞ\005", line=-1051565728)
    at /usr/src/sys/kern/kern_mutex.c:332
#5  0xc0180fa7 in fxp_poll (ifp=0xc038be2c, cmd=3243401568, count=0)
    at /usr/src/sys/dev/fxp/if_fxp.c:1465
#6  0xc0181161 in fxp_intr (xsc=0xc1526000) at
/usr/src/sys/dev/fxp/if_fxp.c:1516
#7  0xc01c4f72 in ithread_loop (arg=0xc4016200) at
/usr/src/sys/kern/kern_intr.c:537
#8  0xc01c3f60 in fork_exit (callout=0xc4014f00, arg=0x0, frame=0x0)
    at /usr/src/sys/kern/kern_fork.c:792


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Robin P. Blanchard
Systems Integration Specialist
Georgia Center for Continuing Education
fon: 706.542.2404 <|> fax: 706.542.6546
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