openbsd test error: kernel: protection fault trap, code=NUM

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 399b2cc5683e vio: Unlock, switch to qstart function
git tree: openbsd
console output: https://syzkaller.appspot.com/x/log.txt?x=167015c0580000
kernel config: https://syzkaller.appspot.com/x/.config?x=1bc15e68cd2a49e5
dashboard link: https://syzkaller.appspot.com/bug?extid=69d974370cd55b0cd1b9

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/75c3ac9ddfc3/disk-399b2cc5.raw.xz
bsd.gdb: https://storage.googleapis.com/syzbot-assets/ba3d1657de79/bsd-399b2cc5.gdb.xz
kernel image: https://storage.googleapis.com/syzbot-assets/fda153ac94a4/kernel-399b2cc5.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+69d974...@syzkaller.appspotmail.com

kernel: protection fault trap, code=0

Stopped at vio_populate_rx_mbufs+0xae: movl 0x8(%r13),%esi

ddb> serialport: Connected to syzkaller.us-central1-b.ci-openbsd-main-test-2 port 1 (session ID: decc6ecb395c8bf68ff3c2a544395e77bb515a8eb98e4b5b62c6782099cecbcc, active connections: 1).


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