doc: add section about how *not* to rename device nodes

Thanks to Mario 'BitKoenig' Holbe <Mario.Holbe@tu-ilmenau.de>.

diff --git a/udev/udev.xml b/udev/udev.xml
index d3fa76a9d8baf00c293b4787cbab130b1cc2307e..192a6f1238d806c642322c774d65e469e7f6ad7e 100644 (file)
--- a/udev/udev.xml
+++ b/udev/udev.xml
@@ -297,8 +297,13 @@
             <varlistentry>
               <term><option>NAME</option></term>
               <listitem>
             <varlistentry>
               <term><option>NAME</option></term>
               <listitem>

-                <para>The name of the node to be created, or the name the network interface
-                should be renamed to.</para>
+                <para>The name, a network interface should be renamed to, or the name
+                a device node should be named. Usually the kernel provides the defined
+                node name, or even creates and removes the node before udev receives
+                any event. Changing the node name from the kernel's default may result
+                in unexpected behavior and is not supported. Udev is only expected to
+                handle device node permissions and to create additional symlinks, which
+                do not conflict with the kernel device node names.</para>

               </listitem>
             </varlistentry>
 
               </listitem>
             </varlistentry>
 


@@ -306,9 +311,16 @@
               <term><option>SYMLINK</option></term>
               <listitem>
                 <para>The name of a symlink targeting the node. Every matching rule will add
               <term><option>SYMLINK</option></term>
               <listitem>
                 <para>The name of a symlink targeting the node. Every matching rule will add

-                this value to the list of symlinks to be created along with the device  node.
+                this value to the list of symlinks to be created along with the device node.

                 Multiple symlinks may be specified by separating the names by the space
                 Multiple symlinks may be specified by separating the names by the space

-                character.</para>
+                character. In case multiple devices claim the same name, the link will
+                always point to the device with the highest link_priority. If the current device
+                goes away, the links will be re-evaluated and the device with the next highest
+                link_priority will own the link. If no link_priority is specified, the order
+                of the devices, and which of them will own the link, is undefined. Claiming
+                the same name for a node and links may result in unexpected behavior and is
+                not supported.
+                </para>

               </listitem>
             </varlistentry>
 
               </listitem>
             </varlistentry>