netbsd boot error: panic: LOCKDEBUG: Mutex error: _mutex_init,363: already initialized

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 4941a3c9 G/c unused rwlock owner macros copy-pasted from t..
git tree: netbsd
console output: https://syzkaller.appspot.com/x/log.txt?x=149f3da9e00000
kernel config: https://syzkaller.appspot.com/x/.config?x=824b23e1f4b6c76b
dashboard link: https://syzkaller.appspot.com/bug?extid=5a77339dc0a55e8d8caa
compiler: g++ (Ubuntu 5.4.0-6ubuntu1~16.04.12) 5.4.0 20160609

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+5a7733...@syzkaller.appspotmail.com

[ 1.0000000] panic: LOCKDEBUG: Mutex error: _mutex_init,363: already
initialized
[ 1.0000000] cpu0: Begin traceback...
[ 1.0000000] vpanic() at netbsd:vpanic+0x2aa sys/kern/subr_prf.c:336
[ 1.0000000] snprintf() at netbsd:snprintf
[ 1.0000000] lockdebug_abort1() at netbsd:lockdebug_abort1+0x16e
sys/kern/subr_lockdebug.c:799
[ 1.0000000] lockdebug_alloc() at netbsd:lockdebug_alloc+0x155
sys/kern/subr_lockdebug.c:265
[ 1.0000000] _mutex_init() at netbsd:_mutex_init+0x89 _mutex_init
sys/kern/kern_mutex.c:364 [inline]
[ 1.0000000] _mutex_init() at netbsd:_mutex_init+0x89
sys/kern/kern_mutex.c:345
[ 1.0000000] sleeptab_init() at netbsd:sleeptab_init+0x60
sys/kern/kern_sleepq.c:83
[ 1.0000000] main() at netbsd:main+0x216 sys/kern/init_main.c:433
[ 1.0000000] cpu0: End traceback...
[ 1.0000000] fatal breakpoint trap in supervisor mode
[ 1.0000000] trap type 1 code 0 rip 0xffffffff8021dd9d cs 0x8 rflags
0x202 cr2 0 ilevel 0x8 rsp 0xffffffff8625dc60
[ 1.0000000] curlwp 0xffffffff85345b80 pid 0.1 lowest kstack
0xffffffff862592c0
Stopped in pid 0.1 (system) at netbsd:breakpoint+0x5: leave
db{0}>


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