Remove obsolete text referring to "patchlevels" in source packages

Before 2011, kernel udebs were built from separate source packages,
and dak didn't support Built-Using.  This meant there was no guarantee
that the exact source version for the kernel udebs in a suite would be
present in the same suite.

To ensure that we could comply with the GPL's requirements for source
availability, the kernel patch system supported multiple series files
that could each add and remove patch files.  Each Debian revision
based on the same upstream version would add a new series file, and
the source could be patched to the current or an older "patchlevel".

This became obsolete once we started building kernel udebs directly,
and the patch system has since been entirely replaced with quilt.

chapter-common-tasks.dbk

@@ -5,8 +5,7 @@
 <title>Common kernel-related tasks</title>
 <section id="s-common-getting"><title>Obtaining the Debian kernel source</title>
 <para>
-To get the Debian kernel source at the current maximum patchlevel, it is
-sufficient to install the latest
+To get the Debian kernel source, it is sufficient to install the latest
 <package>linux-source-<replaceable>version</replaceable></package> package and unpack
 the source, for example:
 </para>
@@ -293,10 +292,7 @@ This will install the packages required by the kernel build process.
 <para>
 This will download and unpack the <package>linux</package> source package,
 making the tree available in the
-<filename>linux-<replaceable>version</replaceable></filename> directory.  As always,
-the revision part of the version of this package (for example, 1 in 3.2.19-1)
-will determine its patchlevel with respect to the original upstream kernel
-source.
+<filename>linux-<replaceable>version</replaceable></filename> directory.
 </para>
 </listitem>
 </varlistentry>

chapter-packaging.dbk

@@ -22,11 +22,8 @@ of the binary packages built from these source packages.
 <term><package>linux-source-<replaceable>version</replaceable></package></term>
 <listitem>
 <para>
-This package contains the Debian kernel source tarball.  The patchlevel of the
-source is determined by the Debian revision of the package, for example the
-version 4.2.5-1 of the package <package>linux-source-4.2</package> contains
-the version 4.2.5 of the Debian kernel source patched to patchlevel 1.  Once
-the package is installed, the source tarball is available at
+This package contains the Debian kernel source tarball.  Once the
+package is installed, the source tarball is available at
 <filename>/usr/src/linux-source-<replaceable>version</replaceable>.tar.xz</filename>.
 </para>
 </listitem>

chapter-source.dbk

@@ -41,14 +41,7 @@ the source from
 <filename>linux_<replaceable>version</replaceable>.orig.tar.xz</filename> (that is,
 pristine kernel source with problematic parts removed) and applying a set of
 Debian patches.  These patches typically implement essential fixes for serious
-bugs and security holes.  The Debian version of the kernel packages has the
-form <replaceable>version</replaceable><literal>-</literal><replaceable>revision</replaceable> where
-<replaceable>version</replaceable> is the upstream version of the
-kernel (like 3.2.20) and <replaceable>revision</replaceable>
-determines the patchlevel.  For example, the packages with version 3.2.20-1 are
-built from the <filename>linux_3.2.20.orig.tar.xz</filename> source, patched up
-to patchlevel 1.  Certain packages include extra 'featuresets' not included in
-the upstream source, such as <literal>rt</literal>.
+bugs and security holes.
 </para>
 </section>
 

debian/changelog

@@ -3,6 +3,7 @@ kernel-handbook (1.0.21) UNRELEASED; urgency=medium
   * Try to reduce pain points in rebuilding official kernel packages
     (Closes: #1022061):
     - Reorder sections in "Common kernel-related tasks" to reduce confusion
+  * Remove obsolete text referring to "patchlevels" in source packages
 
  -- Ben Hutchings <benh@debian.org>  Mon, 01 May 2023 22:48:21 +0200