Add explicit FAQ about "fatal trap 12" errors, and what to do with them.

Point to the harder-to-find "kernel panic troubleshooting" FAQ.

en_US.ISO8859-1/books/faq/book.sgml

@@ -3936,6 +3936,26 @@ quit</programlisting>
           </answer>
         </qandaentry>
 
+        <qandaentry>
+          <question id="trap-12-panic">
+            <para>My system crashes with the message <errorname>Fatal
+              trap 12: page fault in kernel mode</errorname> and a
+              bunch of information.  What should I do?</para>
+          </question>
+
+          <answer>
+            <para>The FreeBSD developers are very interested in these
+              errors, but need some more information than just the
+              error you see.  Copy your full crash message.  Then
+              consult the FAQ section on <link linkend=
+              "KERNEL-PANIC-TROUBLESHOOTING">kernel panics</link>,
+              build a debugging kernel, and get a backtrace.  This
+              might sound difficult, but you don't need any
+              programming skills; you just have to follow the
+              instructions.</para>
+          </answer>
+        </qandaentry>
+
         <qandaentry>
           <question id="screen-loses-sync">
             <para>Why does the screen go black and lose sync when I