System Hang

[Nicholas Bernstein]

hello all,
I'm hoping someone can give me a hand with this. I have a suspicion as
to what is causing this, but I don't want to "taint" any replies I get.
If any of knowledgeable folks out there could help me out, offer
possible areas to look into, better places to contact, or anything that
could possibly be helpful, I would really, really appreciate it. 

					thanks in advance,
					Nick
Info follows: 


System: 
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HP Proliant DL140 
http://h18004.www1.hp.com/products/servers/proliantdl140/index.html
FreeBSD 5.2-CURRENT #0 standard kernel
2 xeon (hyperthreaded) processors

Problem Description: 
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System becomes unresponsive and "hangs". System does not respond to
keyboard, network or any other type of input. 


Error Message:
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panic: Assertion TD_ON_SLEEPQ(td) failed at
/usr/src/sys/kern/subr_sleepqueue.c:783 at line 783 in file:
/usr/src/sys/kern/subr_sleepqueue.c
cpuid=1
Debugger("panic")
Spin lick sched lock held by 0x617eb00 for > 5

Related info:
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/usr/src/sys/kern/subr_sleepqueue.c:
...
    770 /*
    771  * Abort a thread as if an interrupt had occured.  Only abort
    772  * interruptable waits (unfortunately it isn't safe to abort
others).
    773  *
    774  * XXX: What in the world does the comment below mean?
    775  * Also, whatever the signal code does...
    776  */
    777 void
    778 sleepq_abort(struct thread *td)
    779 {
    780         void *wchan;
    781
    782         mtx_assert(&sched_lock, MA_OWNED);
    783         MPASS(TD_ON_SLEEPQ(td));
    784         MPASS(td->td_flags & TDF_SINTR);
    785
    786         /*
    787          * If the TDF_TIMEOUT flag is set, just leave. A
    788          * timeout is scheduled anyhow.
    789          */
    790         if (td->td_flags & TDF_TIMEOUT)
    791                 return;
    792
    793         CTR3(KTR_PROC, "sleepq_abort: thread %p (pid %d, %s)",
td,
    794             td->td_proc->p_pid, td->td_proc->p_comm);
    795         wchan = td->td_wchan;
    796         mtx_unlock_spin(&sched_lock);
    797         sleepq_remove(td, wchan);
    798         mtx_lock_spin(&sched_lock);
    799 } 


Also, in order for the machine to detect it's broadcom 5700 network
cards, I had to the line 
	acpi_load="no"
to my /boot/loader.conf. Upon reboot the network cards show up in an
ifconfig and work perfectly. 


Possible references:
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This isn't the exact same error, but it's the closest thing I could find
to my error: 

http://lists.freebsd.org/pipermail/freebsd-current/2004-March/022633.html

This error is also pretty close, but not the same thing:

http://groups.google.com/groups?q=%27panic:+Assertion+TD_ON_SLEEPQ(td)+failed+at%27&hl=en&lr=&ie=UTF-8&safe=off&selm=200405182105.04275.thierry%40herbelot.com&rnum=1


				. . . 
		Thanks for taking the time to read this. 
				. . . 

-- 
Nicholas Bernstein, Unix Systems Administrator
Document Systems Inc.
http://docmagic.com
nick at docmagic.com