assert "scan->kqs_start.kn_filter == EVFILT_MARKER" failed in kern_event.c

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 17449d5ce459 Add SPI clocks for other 64-bit Rockchip SoCs.
git tree: openbsd
console output: https://syzkaller.appspot.com/x/log.txt?x=149aa586180000
kernel config: https://syzkaller.appspot.com/x/.config?x=7058272de1526588
dashboard link: https://syzkaller.appspot.com/bug?extid=682b992f986dc9dce50d

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/9410a011fb48/disk-17449d5c.raw.xz
bsd.gdb: https://storage.googleapis.com/syzbot-assets/e8f5e54a96aa/bsd-17449d5c.gdb.xz
kernel image: https://storage.googleapis.com/syzbot-assets/a0decc52f919/kernel-17449d5c.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+682b99...@syzkaller.appspotmail.com

panic: kernel diagnostic assertion "scan->kqs_start.kn_filter == EVFILT_MARKER" failed: file "/syzkaller/managers/multicore/kernel/sys/kern/kern_event.c", line 1564
Starting stack trace...
panic(ffffffff828aa32f) at panic+0x16f sys/kern/subr_prf.c:229
__assert(ffffffff8292f138,ffffffff8291e1a4,61c,ffffffff828c64ff) at __assert+0x29 sys/kern/subr_prf.c:157
kqueue_scan_finish(ffff80002edb6ff0) at kqueue_scan_finish+0x14c sys/kern/kern_event.c:1565
sys_kevent(0,0,0) at sys_kevent+0x6b6 sys/kern/kern_event.c:1076
end trace frame: 0x0, count: 253
End of stack trace.


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