kern/51737: uninitialized lock with sysmon during shutdown

[mlelstv%serpens.de@localhost]

>Number:         51737
>Category:       kern
>Synopsis:       uninitialized lock with sysmon during shutdown
>Confidential:   no
>Severity:       critical
>Priority:       low
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Fri Dec 23 14:35:00 +0000 2016
>Originator:     mlelstv
>Release:        NetBSD 7.99.52
>Organization:
	
>Environment:
	
	
System: NetBSD beeky.local 7.99.52 NetBSD 7.99.52 (BEEKY) #29: Fri Dec 23 14:22:58 CET 2016 mlelstv@gossam:/home/netbsd-current/obj.sparc64/home/netbsd-current/src/sys/arch/sparc64/compile/BEEKY sparc64
Architecture: sparc64
Machine: sparc64
>Description:
During shutdown a LOCKDEBUG kernel panicked with:

panic: lockdebug_lookup: uninitialized lock (lock=0x101de9bd0, from=012da9d8)

While the backtrace command from ddb didn't print anything, the sync
command revealed the following backtrace:

Frame pointer is at 0x158968751
Call traceback:
 netbsd:cpu_reboot+0x1b4(a, 63, 0, 158969077, 1c98400, 1ca0348) fp = 158968811
 netbsd:db_sync_cmd+0x20(100, 0, 1cce400, 1cdcc00, f, 101de7900) fp = 1589688c1
 netbsd:db_command+0xa8(fffffffffffffffa, 0, 73, 158969230, 2, 73) fp = 158968971
 netbsd:db_command_loop+0xa4(1c67460, 0, 1cce400, 1c67000, 1836f68, 1c8b3a8) fp = 158968ab1
 netbsd:db_trap+0x104(105d348, 0, 18f26c0, 1c67400, 1cce400, 1c67460) fp = 158968b91
 netbsd:kdb_trap+0xdc(101, 0, 0, e0048000, 1ccf400, 0) fp = 158968c51
 netbsd:trap+0x4cc(101, 158969750, f, 1c03c00, 1c00000, 1cf5000) fp = 158968d01
 netbsd:10110cc+0(158969750, 101, 105d340, 1d0006, 1c8b3a8, e0048000) fp = 158968ea1
 netbsd:vpanic+0x168(18f26c0, 1cf51e8, 1915398, 158969a78, 1cf5368, 1c67400) fp = 158969081
 netbsd:panic+0x24(1915398, 158969a78, 1cf3c00, 1cf5000, 4, 1cf51e8) fp = 158969131
 netbsd:lockdebug_wantlock+0x1d4(1915398, 101de9bd0, 12da9d8, 15825a0, 1871f28, 0) fp = 1589691f1
 netbsd:mutex_enter+0x600(101de9bd0, 12da9d8, 0, 101de7900, 2014000, 0) fp = 1589692a1
 netbsd:sysmon_envsys_acquire+0x58(101de9bd0, 1cb9850, 190d800, 15825a0, 1871f28, 101fa2de8) fp = 158969361
 netbsd:sysmon_envsys_get_max_value+0x28(101de9bd0, 0, 12dbfcc, 1915400, 2014000, 101de9b08) fp = 158969411
 netbsd:tda_adjust+0x10(1028780, 0, 0, 101de9b08, 101de7900, 2014000) fp = 1589694c1
 netbsd:sysmon_task_queue_thread+0x64(10242b8c8, 1cb92e0, 101dbce00, 190a800, af0b8, 10242b8c8) fp = 158969571
 netbsd:lwp_trampoline+0x8(1cb9000, 1cb9000, 1cb92b8, 1c64928, 1cb92e0, 101daa298) fp = 158969621
 netbsd:100030+0(f00587f4, fff3dcb8, 112c00, 111fc0, fff3ddb8, 1) fp = fff3d651


>How-To-Repeat:
Did happen the first time and couldn't be repeated.

>Fix:
	

>Unformatted: