+ OVERLAY=/syzkaller/userspace/overlay
+ sync
+ doas umount /altroot
umount: /altroot: not currently mounted
+ true
+ doas vnconfig -u vnd0
vnconfig: VNDIOCCLR: Device not configured
+ true
+ doas /sbin/vnconfig vnd0 image
+ doas mount /dev/vnd0a /altroot
+ doas cp kernel /altroot/bsd
+ test -d /syzkaller/userspace/overlay
+ sync
+ doas umount /altroot
umount: /altroot: Device busy