doc: ReSTify SELinux.txt

Adjusts for ReST markup and moves under LSM admin guide.

Cc: Paul Moore <paul@paul-moore.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Documentation/admin-guide/LSM/SELinux.rst

@@ -0,0 +1,33 @@
+=======
+SELinux
+=======
+
+If you want to use SELinux, chances are you will want
+to use the distro-provided policies, or install the
+latest reference policy release from
+
+	http://oss.tresys.com/projects/refpolicy
+
+However, if you want to install a dummy policy for
+testing, you can do using ``mdp`` provided under
+scripts/selinux.  Note that this requires the selinux
+userspace to be installed - in particular you will
+need checkpolicy to compile a kernel, and setfiles and
+fixfiles to label the filesystem.
+
+	1. Compile the kernel with selinux enabled.
+	2. Type ``make`` to compile ``mdp``.
+	3. Make sure that you are not running with
+	   SELinux enabled and a real policy.  If
+	   you are, reboot with selinux disabled
+	   before continuing.
+	4. Run install_policy.sh::
+
+		cd scripts/selinux
+		sh install_policy.sh
+
+Step 4 will create a new dummy policy valid for your
+kernel, with a single selinux user, role, and type.
+It will compile the policy, will set your ``SELINUXTYPE`` to
+``dummy`` in ``/etc/selinux/config``, install the compiled policy
+as ``dummy``, and relabel your filesystem.

Documentation/admin-guide/LSM/index.rst

@@ -29,3 +29,8 @@ will always include the capability module. The list reflects the
 order in which checks are made. The capability module will always
 be first, followed by any "minor" modules (e.g. Yama) and then
 the one "major" module (e.g. SELinux) if there is one configured.
+
+.. toctree::
+   :maxdepth: 1
+
+   SELinux