diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt
index 0d07513..e418f3d 100644
--- a/Documentation/filesystems/proc.txt
+++ b/Documentation/filesystems/proc.txt
@@ -188,6 +188,12 @@
 contains details information about the process itself.  Its fields are
 explained in Table 1-4.
 
+(for SMP CONFIG users)
+For making accounting scalable, RSS related information are handled in
+asynchronous manner and the vaule may not be very precise. To see a precise
+snapshot of a moment, you can see /proc/<pid>/smaps file and scan page table.
+It's slow but very precise.
+
 Table 1-2: Contents of the statm files (as of 2.6.30-rc7)
 ..............................................................................
  Field                       Content