Add a note to snapshot.txt that the origin target must be suspended when
loading or unloading the snapshot target.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
snapshots less metadata must be saved on disk - they can be kept in
memory by the kernel.
+When loading or unloading the snapshot target, the corresponding
+snapshot-origin or snapshot-merge target must be suspended. A failure to
+suspend the origin target could result in data corruption.
+
* snapshot-merge <origin> <COW device> <persistent> <chunksize>