docs: virt: user_mode_linux.rst: update compiling instructions

Instead of pointing for a pre-2.4 and a seaparate patch,
update it to match current upstream, as UML was merged
a long time ago.

Signed-off-by: Mauro Carvalho Chehab <[e-mail]>
Signed-off-by: Paolo Bonzini <[e-mail]>

Documentation/virt/uml/user_mode_linux.rst

···
 =====================
 
 :Author:  User Mode Linux Core Team
-:Last-updated: Mon Nov 18 14:16:16 EST 2002
+:Last-updated: Sat Jan 25 16:07:55 CET 2020
 
 This document describes the use and abuse of Jeff Dike's User Mode
 Linux: a port of the Linux kernel as a normal Intel Linux process.
···
 
 
   Compiling the user mode kernel is just like compiling any other
-  kernel.  Let's go through the steps, using 2.4.0-prerelease (current
-  as of this writing) as an example:
+  kernel.
 
 
-  1. Download the latest UML patch from
-     the download page <http://user-mode-linux.sourceforge.net/
-
-     In this example, the file is uml-patch-2.4.0-prerelease.bz2.
-
-
-  2. Download the matching kernel from your favourite kernel mirror,
+  1. Download the latest kernel from your favourite kernel mirror,
      such as:
 
-     ftp://ftp.ca.kernel.org/pub/kernel/v2.4/linux-2.4.0-prerelease.tar.bz2
+     https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/linux-5.4.14.tar.xz
 
-
-  3. Make a directory and unpack the kernel into it::
+  2. Make a directory and unpack the kernel into it::
 
        host%
        mkdir ~/uml
···
        cd ~/uml
 
        host%
-       tar -xzvf linux-2.4.0-prerelease.tar.bz2
+       tar xvf linux-5.4.14.tar.xz
 
 
-
-  4. Apply the patch using::
-
-       host%
-       cd ~/uml/linux
-
-       host%
-       bzcat uml-patch-2.4.0-prerelease.bz2 | patch -p1
-
-
-
-  5. Run your favorite config; ``make xconfig ARCH=um`` is the most
+  3. Run your favorite config; ``make xconfig ARCH=um`` is the most
      convenient.  ``make config ARCH=um`` and ``make menuconfig ARCH=um``
      will work as well.  The defaults will give you a useful kernel.  If
      you want to change something, go ahead, it probably won't hurt
···
 
 
 
-  6. Finish with ``make linux ARCH=um``: the result is a file called
+  4. Finish with ``make linux ARCH=um``: the result is a file called
      ``linux`` in the top directory of your source tree.
-
-  Make sure that you don't build this kernel in /usr/src/linux.  On some
-  distributions, /usr/include/asm is a link into this pool.  The user-
-  mode build changes the other end of that link, and things that include
-  <asm/anything.h> stop compiling.
-
-  The sources are also available from cvs at the project's cvs page,
-  which has directions on getting the sources. You can also browse the
-  CVS pool from there.
-
-  If you get the CVS sources, you will have to check them out into an
-  empty directory. You will then have to copy each file into the
-  corresponding directory in the appropriate kernel pool.
-
-  If you don't have the latest kernel pool, you can get the
-  corresponding user-mode sources with::
-
-
-       host% cvs co -r v_2_3_x linux
-
-
-
-
-  where 'x' is the version in your pool. Note that you will not get the
-  bug fixes and enhancements that have gone into subsequent releases.
 
 
 2.2.  Compiling and installing kernel modules
···
 3.1.  Running UML
 -----------------
 
-  It runs on 2.2.15 or later, and all 2.4 kernels.
+  It runs on 2.2.15 or later, and all kernel versions since 2.4.
 
 
   Booting UML is straightforward.  Simply run 'linux': it will try to