panic: kernel diagnostic assertion "refs != ~NUM" failed: file

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 691001c74c47 Fix inverted logic in bus_dmamap_load() and i..
git tree: openbsd
console output: https://syzkaller.appspot.com/x/log.txt?x=100a409c580000
kernel config: https://syzkaller.appspot.com/x/.config?x=7058272de1526588
dashboard link: https://syzkaller.appspot.com/bug?extid=20a1a2e3fe065f9edeb9

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/49514deac7c2/disk-691001c7.raw.xz
bsd.gdb: https://storage.googleapis.com/syzbot-assets/494156fdbe9a/bsd-691001c7.gdb.xz
kernel image: https://storage.googleapis.com/syzbot-assets/7d6f7eb11b5f/kernel-691001c7.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+20a1a2...@syzkaller.appspotmail.com

login: panic: kernel diagnostic assertion "refs != ~0" failed: file


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