netbsd boot error: panic: LOCKDEBUG: Mutex error: mutex_vector_enter,514: spin lock held

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 071ae129 pull in atomicity.h (atomicity.cc) on sparc. 3 o..
git tree: netbsd
console output: https://syzkaller.appspot.com/x/log.txt?x=135d5627e00000
kernel config: https://syzkaller.appspot.com/x/.config?x=19c26c7ba7ac2db1
dashboard link: https://syzkaller.appspot.com/bug?extid=e3be1d59f451bda5b95c
compiler: clang version 3.8.0-2ubuntu4 (tags/RELEASE_380/final)

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+e3be1d...@syzkaller.appspotmail.com

[ 5.6144615] panic: LOCKDEBUG: Mutex error: mutex_vector_enter,514: spin lock held
[ 5.6180308] cpu1: Begin traceback...
[ 5.6251753] vpanic() at netbsd:vpanic+0x7c1 sys/kern/subr_prf.c:334
[ 5.6394558] panic() at netbsd:panic+0x1ad sys/kern/subr_prf.c:255
[ 5.6537301] lockdebug_abort1() at netbsd:lockdebug_abort1+0xd12
[ 5.6715773] mutex_enter() at netbsd:mutex_enter+0x5e4 sys/kern/kern_mutex.c:517
[ 5.6894250] vmem_rehash_all() at netbsd:vmem_rehash_all+0x6df sys/kern/subr_vmem.c:1437
[ 5.7072658] workqueue_worker() at netbsd:workqueue_worker+0x3d0 workqueue_runlist sys/kern/subr_workqueue.c:104 [inline]
[ 5.7072658] workqueue_worker() at netbsd:workqueue_worker+0x3d0 sys/kern/subr_workqueue.c:133
[ 5.7108374] cpu1: End traceback...
[ 5.7143991] fatal breakpoint trap in supervisor mode
[ 5.7143991] trap type 1 code 0 rip 0xffffffff8022025d cs 0x8 rflags 0x246 cr2 0x791f65d34f03 ilevel 0x8 rsp 0xffffb1007a1c9920
[ 5.7179628] curlwp 0xffffb10010c79280 pid 0.29 lowest kstack 0xffffb1007a1c22c0
Stopped in pid 0.29 (system) at netbsd:breakpoint+0x5: leave
db{1}>


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