2.4.17-rc2

 Documentation

diff -Naur -X /home/marcelo/lib/dontdiff linux-2.4.16/Documentation/DMA-mapping.txt linux/Documentation/DMA-mapping.txt
--- linux-2.4.16/Documentation/DMA-mapping.txt   Fri Oct 12 22:35:53 2001
+++ linux/Documentation/DMA-mapping.txt   Thu Dec  6 15:47:19 2001
@@ -60,6 +60,9 @@
 might be mapped somewhere entirely different than the rest of physical
 memory.
 
+Also, this means that you cannot take the return of a kmap()
+call and DMA to/from that.  This is similar to vmalloc().
+
 What about block I/O and networking buffers?  The block I/O and
 networking subsystems make sure that the buffers they use are valid
 for you to DMA from/to.