panic with LOCKDEBUG

[Christoph Egger <Christoph_Egger%gmx.de@localhost>]

Hi!

An amd64 GENERIC kernel 4.99.63 with LOCKDEBUG panics by just typing "envstat"

$ envstat
Reader / writer lock error: lockdebug_wantlock: locking against myself

lock address : 0xffff80004bc51fa0 type     :     sleep/adaptive
shared holds :                  1 exclusive:                  0
shares wanted:                  1 exclusive:                  0
current cpu  :                  1 last held:                  1
current lwp  : 0xffff800050314460 last held: 0xffff800050314460
last locked  : 0xffffffff8070df1a unlocked : 0xffffffff8070df57
initialized  : 0xffffffff8070e9af
owner/count  : 0x0000000000000010 flags    : 0x0000000000000008

Turnstile chain at 0xffffffff80c7ec00.
=> No active turnstile for this lock.

panic: LOCKDEBUG
Stopped in pid 605.1 (envstat) at       netbsd:breakpoint+0x5:  leave
db{1}> bt
breakpoint() at netbsd:breakpoint+0x5
panic() at netbsd:panic+0x257
lockdebug_abort1() at netbsd:lockdebug_abort1+0xd3
rw_vector_enter() at netbsd:rw_vector_enter+0x2f1
prop_dictionary_iterator() at netbsd:prop_dictionary_iterator+0x77
prop_dictionary_iterator() at netbsd:prop_dictionary_iterator+0x14a
prop_dictionary_externalize() at netbsd:prop_dictionary_externalize+0x40
__main() at netbsd:__main+0x13e
sysmonioctl_envsys() at netbsd:sysmonioctl_envsys+0x4da
VOP_IOCTL() at netbsd:VOP_IOCTL+0x6b
vn_ioctl() at netbsd:vn_ioctl+0x6d
sys_ioctl() at netbsd:sys_ioctl+0x134
syscall() at netbsd:syscall+0x9a
db{1}>