kern/121322: 'panic: spin lock held too long' on reboot

[Kris Kennaway]

The following reply was made to PR kern/121322; it has been noted by GNATS.

From: Kris Kennaway <kris at FreeBSD.org>
To: Lars Stokholm <lars.stokholm at gmail.com>
Cc: freebsd-gnats-submit at FreeBSD.org
Subject: Re: kern/121322: 'panic: spin lock held too long' on reboot
Date: Mon, 03 Mar 2008 21:56:52 +0100

 Lars Stokholm wrote:
 >> Number:         121322
 >> Category:       kern
 >> Synopsis:       'panic: spin lock held too long' on reboot
 >> Confidential:   no
 >> Severity:       serious
 >> Priority:       medium
 >> Responsible:    freebsd-bugs
 >> State:          open
 >> Quarter:        
 >> Keywords:       
 >> Date-Required:
 >> Class:          sw-bug
 >> Submitter-Id:   current-users
 >> Arrival-Date:   Mon Mar 03 16:00:01 UTC 2008
 >> Closed-Date:
 >> Last-Modified:
 >> Originator:     Lars Stokholm
 >> Release:        FreeBSD 7-STABLE
 >> Organization:
 >> Environment:
 > FreeBSD stokholm 7.0-STABLE FreeBSD 7.0-STABLE #2: Sun Mar  2 20:47:23 CET 2008     lars at stokholm:/usr/obj/usr/src/sys/STOKHOLM  i386
 >> Description:
 > After I enabled my processor's hyper threading capability, I'm beginning to get this, sometimes when I reboot:
 > 
 > Rebooting...
 > cpu_reset: Stopping other CPUs
 > spin lock 0xc0c1ea40 (sched lock 0) held by 0xc2d9ecc0 (tid 100001) too long
 > panic: spin lock held too long
 > cpuid = 0
 > 
 > Needless to say, after which I have to cut the power manually.
 > 
 > My processor is a Pentium 4 with hyper threading.
 
 Can you enable WITNESS and DDB and reproduce the problem?  It will drop 
 into the debugger and you can do 'show locks' to show who holds it, then 
 'bt <#>' that thread.
 
 > Here's my kernel config:
 > include         GENERIC
 > ident           STOKHOLM
 > nooptions       SCHED_4BSD
 > options         SCHED_ULE
 > device          snd_ich
 > device          speaker
 > device          sound
 
 Kris