kern/38649: locking prboblem with ptrace on SMP machines

[martin%duskware.de@localhost]

>Number:         38649
>Category:       kern
>Synopsis:       locking prboblem with ptrace on SMP machines
>Confidential:   no
>Severity:       critical
>Priority:       high
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Tue May 13 08:40:00 +0000 2008
>Originator:     Martin Husemann
>Release:        NetBSD 4.99.62
>Organization:
The NetBSD Foundation, Inc.
>Environment:
System: NetBSD martins.aprisoft.de 4.99.62 NetBSD 4.99.62 (MARTINS) #2: Mon May 
12 15:40:19 CEST 2008 
martin%martins.aprisoft.de@localhost:/usr/src/sys/arch/amd64/compile/MARTINS 
amd64
Architecture: x86_64
Machine: amd64
>Description:

Run "gdb -p ..." on a -current SMP system with LOCKDEBUG kernel:

Mutex error: mutex_vector_exit: assertion failed: MUTEX_OWNER(mtx->mtx_owner) 
== curthread
          
lock address : 0xffff80004bc86500 type     :     sleep/adaptive
shared holds :                  0 exclusive:                  0
shares wanted:                  0 exclusive:                  0
current cpu  :                  1 last held:                  1
current lwp  : 0xffff80004fdc2b60 last held: 000000000000000000
last locked  : 0xffffffff80266793 unlocked : 0xffffffff802667c7
initialized  : 0xffffffff802255ae                              
owner field  : 000000000000000000 wait/spin:                0/0
                                                               
Turnstile chain at 0xffffffff80558700.
=> No active turnstile for this lock. 
                                     
panic: LOCKDEBUG
Stopped in pid 776.1 (gdb) at   netbsd:breakpoint+0x5:  leave


>How-To-Repeat:
s/a

>Fix:
n/a