diff --git a/Documentation/power/freezing-of-tasks.txt b/Documentation/power/freezing-of-tasks.txt
index 04dc1cf..d5c65e8 100644
--- a/Documentation/power/freezing-of-tasks.txt
+++ b/Documentation/power/freezing-of-tasks.txt
@@ -81,7 +81,16 @@
 The majority of these are user space processes, but if any of the kernel threads
 may cause something like this to happen, they have to be freezable.
 
-2. The second reason is to prevent user space processes and some kernel threads
+2. Next, to create the hibernation image we need to free a sufficient amount of
+memory (approximately 50% of available RAM) and we need to do that before
+devices are deactivated, because we generally need them for swapping out.  Then,
+after the memory for the image has been freed, we don't want tasks to allocate
+additional memory and we prevent them from doing that by freezing them earlier.
+[Of course, this also means that device drivers should not allocate substantial
+amounts of memory from their .suspend() callbacks before hibernation, but this
+is e separate issue.]
+
+3. The third reason is to prevent user space processes and some kernel threads
 from interfering with the suspending and resuming of devices.  A user space
 process running on a second CPU while we are suspending devices may, for
 example, be troublesome and without the freezing of tasks we would need some
@@ -111,7 +120,7 @@
 thawed after the driver's .resume() callback has run, so it won't be accessing
 the device while it's suspended.
 
-3. Another reason for freezing tasks is to prevent user space processes from
+4. Another reason for freezing tasks is to prevent user space processes from
 realizing that hibernation (or suspend) operation takes place.  Ideally, user
 space processes should not notice that such a system-wide operation has occurred
 and should continue running without any problems after the restore (or resume