Linux - Troubleshooting the "device is busy"

# umount /dev/dsk/c0t2d0s7
umount: /dev/dsk/c0t2d0s7: device is busy

# fuser -u /dev/dsk/c0t2d0s7
/dev/dsk/c0t2d0s7: 1313co(oracle) 1223c(root)

# fuser -k /dev/dsk/c0t2d0s7
/dev/dsk/c0t2d0s7: 1313co 1223c
-k option to kill all processes using the specified file or filesystem