panic: vwakeup: neg numoutput (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: ddef1afac53e netinet/ip.h: fix IPTOS_DSCP_VA value to be 0..
git tree: openbsd
console output: https://syzkaller.appspot.com/x/log.txt?x=12451d58580000
kernel config: https://syzkaller.appspot.com/x/.config?x=7058272de1526588
dashboard link: https://syzkaller.appspot.com/bug?extid=4e01044a63bd75140335

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/f090a52c6dd8/disk-ddef1afa.raw.xz
bsd.gdb: https://storage.googleapis.com/syzbot-assets/76f8c791f193/bsd-ddef1afa.gdb.xz
kernel image: https://storage.googleapis.com/syzbot-assets/c1fe1b71623a/kernel-ddef1afa.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+4e0104...@syzkaller.appspotmail.com

panic: vwakeup: neg numoutput
Starting stack trace...
panic(ffffffff83386ac3) at panic+0x1d0 sys/kern/subr_prf.c:229
vwakeup(fffffd806c97bea0) at vwakeup+0x17c
biodone(fffffd80640307a8) at biodone+0x121 sys/kern/vfs_bio.c:1290
sd_buf_done(fffffd80097f4360) at sd_buf_done+0x2de sys/scsi/sd.c:772
scsi_done(fffffd80097f4360) at scsi_done+0x40 sys/scsi/scsi_base.c:1496
vioscsi_vq_done(ffff8000000a4268) at vioscsi_vq_done+0xe1 sys/dev/pv/vioscsi.c:-1
intr_handler(ffff80002a252b80,ffff80000006b400) at intr_handler+0x125 sys/arch/amd64/amd64/intr.c:564
Xintr_ioapic_edge23_untramp() at Xintr_ioapic_edge23_untramp+0x18f
Xspllower() at Xspllower+0x1d
msleep_nsec(ffffffff839f9d98,ffffffff83881910,4,ffffffff8341195c,ffffffffffffffff) at msleep_nsec+0x11c sys/kern/kern_synch.c:219
smr_thread(ffff8000ffffca68) at smr_thread+0x17b sys/kern/kern_smr.c:98
end trace frame: 0x0, count: 246
End of stack trace.


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