panic: Mutex error: rw_vector_enter,312: spin lock held

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 9d0dd21c fix -Wsign-compare because module tests trigger it.
git tree: netbsd
console output: https://syzkaller.appspot.com/x/log.txt?x=139fd421e00000
kernel config: https://syzkaller.appspot.com/x/.config?x=6e4d6bd2b8e377a2
dashboard link: https://syzkaller.appspot.com/bug?extid=b6f80eb3c5eab1da21f8
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+b6f80e...@syzkaller.appspotmail.com

login: [ 66.1671762] panic: Mutex error: rw_vector_enter,312: spin lock
held

[ 66.1671762] lock address : 0xffff9c800d92a3c0 type :
spin
[ 66.1671762] initialized : 0xffffffff81199249
[ 66.1671762] shared holds : 0
exclusive: 1
[ 66.1671762] shares wanted: 0
exclusive: 0
[ 66.1671762] current cpu : 1 last
held: 1
[ 66.1671762] current lwp : 0xffff9c8011ae4700 last held:
0xffff9c8011ae4700
[ 66.1671762] last locked* : 0xffffffff811af858 unlocked :
0xffffffff81235379
[ 66.1671762] owner field : 0x0000000000010700 wait/spin:
0/1



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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.