1 files changed, 6 insertions, 0 deletions

diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt
index 2cd920f92e5e..2a99116edc47 100644
--- a/Documentation/filesystems/proc.txt
+++ b/Documentation/filesystems/proc.txt
@@ -2374,8 +2374,14 @@ possible optional fields are:
 
 shared:X  mount is shared in peer group X
 master:X  mount is slave to peer group X
+propagate_from:X  mount is slave and receives propagation from peer group X (*)
 unbindable  mount is unbindable
 
+(*) X is the closest dominant peer group under the process's root.  If
+X is the immediate master of the mount, or if there's no dominant peer
+group under the same root, then only the "master:X" field is present
+and not the "propagate_from:X" field.
+
 For more information on mount propagation see:
 
   Documentation/filesystems/sharedsubtree.txt