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@@ -22,6 +22,8 @@
   table { border-collapse: collapse }
   th { border-bottom: 2pt solid black }
   th, td { padding: 0 6pt }
+  .package { font-family: monospace }
+  var { font-family: sans }
 </style>
 <style type="text/css" media="print">
   .slide { page-break-after: always }
@@ -48,6 +50,7 @@
 
 <div class="slide">
 <h1>The Linux kernel in Debian</h1>
+<object data="tux-debian.svg" width="35%" align="right"></object>
 <h3>Ben Hutchings</h3>
 </div>
 
@@ -86,34 +89,361 @@
 
 <div class="slide">
   <h1>Linux kernel</h1>
+  <ul class="incremental">
+    <li>
+      Started by Linus Torvalds in 1991 as a kernel for i386
+      PCs: <q>just a hobby, won't be big and professional like gnu</q>
+    </li>
+    <li>
+      Adopted as the kernel of the Debian system in 1993
+    </li>
+    <li>
+      After 20 years' development, supports more hardware
+      architectures and devices than anything else
+      <ul class="incremental">
+	<li>
+	  Hardware vendors <em>must</em> provide Linux drivers because
+	  their customers demand it
+	</li>
+      </ul>
+    </li>
+    <li>
+      Still the default kernel for the Debian system
+    </li>
+  </ul>
+</div>
+
+<div class="slide">
+  <h1>Linux release model (1)</h1>
+  <p>
+    The old model:
+  </p>
+  <ul class="incremental">
+    <li>
+      Each stable release had even second component.  Bug fixes and
+      minor features in stable releases with third component
+      incremented (e.g. 2.4.27)
+    </li>
+    <li>
+      Major development done separately, resulting in series of
+      unstable releases with odd second component (e.g. 2.5.50)
+    </li>
+    <li>
+      After a year or two, development resulted in a new stable
+      release
+    </li>
+    <li>
+      Problem: users waited years for new features, and then got many
+      more changes all at once.  Particularly bad in the 2.4-2.6
+      transition.
+    </li>
+  </ul>
 </div>
 
 <div class="slide">
-  <h1>Linux release model</h1>
+  <h1>Linux release model (2)</h1>
+  <p>
+    The new model:
+  </p>
+  <ul class="incremental">
+    <li>
+      Development results in a new stable(-ish) release every 2-3
+      months
+      <ul class="incremental">
+	<li>
+	  git (and previously BitKeeper) made distributed development
+          and testing a lot easier
+	</li>
+      </ul>
+    </li>
+    <li>
+      Each 2.6.<var>x</var> release has stable update branch; releases
+      numbered 2.6.<var>x</var>.<var>y</var>
+      <ul class="incremental">
+	<li>
+	  Usually closed shortly after next stable release, but may
+	  continue as a 'longterm' branch (e.g. 2.6.32.<var>y</var>)
+	</li>
+      </ul>
+    </li>
+    <li>
+      Linux 3.0 doesn't change this, except that <var>x</var> is now
+      the second component and <var>y</var> is the third
+    </li>
+  </ul>
 </div>
 
 <div class="slide">
-  <h1>Debian kernel team</h1>
+  <h1>Debian kernel team (1)</h1>
+  <p>
+    Who are we?
+  </p>
+  <ul class="incremental">
+    <li>
+      Currently 5 general maintainers: Maximilian Attems, Bastian
+      Blank, dann frazier, Moritz Muehlenhoff and me
+    </li>
+    <li>
+      Many more specialised contributors:
+      <ul>
+	<li>Specific architectures</li>
+	<li>Specific features (e.g. Xen)</li>
+	<li>Bug triage</li>
+      </ul>
+    </li>
+    <li>
+      Would appreciate more help, particularly with bug triage and
+      PowerPC
+    </li>
+  </ul>
 </div>
 
 <div class="slide">
-  <h1>Official Linux kernel packages</h1>
+  <h1>Debian kernel team (2)</h1>
+  <p>
+    What do we do?
+  </p>
+  <ul class="incremental">
+    <li>
+      Bug triage - takes a huge amount of time
+    </li>
+    <li>
+      Backport bug fixes and features - particularly new hardware
+      support for stable
+      <ul class="incremental">
+	<li>...while trying not to change kernel ABI in stable</li>
+      </ul>
+    </li>
+    <li>
+      Update build configurations for each new upstream release -
+      e.g. to enable new drivers
+    </li>
+    <li>
+      Try to ensure smooth upgrades when there are major
+      implementation changes - e.g. KMS, switch to libata drivers
+    </li>
+    <li>
+      Integrate <em>some</em> features not accepted upstream
+    </li>
+  </ul>
 </div>
 
 <div class="slide">
-  <h1>Custom Linux kernel packages</h1>
+  <h1>Official Linux kernel packages (1)</h1>
+  <p>
+    Main source package is <span class="package">linux-2.6</span>
+    (still!).  Most binary package names change regularly.
+  </p>
+  <ul class="incremental">
+    <li>
+      <span class="package">linux-image-<var>upstream</var>-<var>abi</var>-<var>flavour</var></span>
+      - compiled kernel and modules
+    </li>
+    <li>
+      <span class="package">linux-headers-<var>upstream</var>-<var>abi</var>-<var>flavour</var></span>
+      (and others) - development package for OOT modules
+    </li>
+    <li>
+      <span class="package">linux-libc-dev</span> - headers for userland
+    </li>
+    <li>
+      <span class="package">linux-source-<var>upstream</var></span> -
+      for custom kernels
+    </li>
+    <li>
+      <span class="package">linux-doc-<var>upstream</var></span>,
+      <span class="package">linux-tools-<var>upstream</var></span>, etc.
+    </li>
+    <li>
+      <span class="package">linux-support-<var>upstream</var>-<var>abi</var></span> -
+      scripts and metadata to support linux-latest-2.6
+    </li>
+  </ul>
+</div>
+
+<div class="slide">
+  <h1>Official Linux kernel packages (2)</h1>
+  <p>
+    The <span class="package">linux-latest-2.6</span> source package builds meta-packages
+    to support automatic upgrades between binaries built
+    from <span class="package">linux-2.6</span>.
+  </p>
+  <ul class="incremental">
+    <li>
+      <span class="package">linux-image-<var>flavour</var></span>
+    </li>
+    <li>
+      <span class="package">linux-headers-<var>flavour</var></span>
+    </li>
+    <li>
+      <span class="package">linux-source</span>,
+      <span class="package">linux-doc</span>,
+      <span class="package">linux-tools</span>, etc.
+    </li>
+  </ul>
+  <p class="incremental">
+    The installer will normally install
+    <span class="package">linux-image-<var>flavour</var></span> (for
+    some appropriate <var>flavour</var>).
+  </p>
+</div>
+
+<div class="slide">
+  <h1>Official Linux kernel packages (3)</h1>
+  <ul class="incremental">
+    <li>
+      <span class="package">firmware-free</span> - separate 'firmware'
+      compliant with DFSG
+    </li>
+    <li>
+      <span class="package">linux-base</span> - base package for
+      images and tools
+    </li>
+    <li>
+      <span class="package">linux-kbuild-2.6</span> builds
+      <span class="package">linux-kbuild-<var>upstream</var></span> -
+      kernel build system and tools for building OOT modules
+    </li>
+  </ul>
+</div>
+
+<div class="slide">
+  <h1>Custom Linux kernel builds</h1>
+  <p>
+    The official packages work for most users, but not all:
+  </p>
+  <ul class="incremental">
+    <li>
+      Different ARM platforms need incompatible configurations,
+      and we cannot build them all
+    </li>
+    <li>
+      New features are not enabled immediately if we are worried
+      about potential regressions
+    </li>
+  </ul>
+  <p class="incremental">
+    Using either upstream source or Debian linux-source package:
+  </p>
+  <ul class="incremental">
+    <li>
+      <span class="package">make && make install</span>
+    </li>
+    <li>
+      <span class="package">make deb-pkg</span> - build packages
+    </li>
+    <li>
+      <span class="package">make-kpkg</span> - build packages with
+      more customisation; requires
+      <span class="package">kernel-package</span>
+    </li>
+  </ul>
+</div>
+
+<div class="slide">
+  <h1>Extra features</h1>
+  <p>
+    Always aim to get patches merged upstream.  But many big features
+    that users want added are <em>not</em> merged upstream for a long
+    time.  Kernel team expects features to be upstream first, then
+    backported.
+  </p>
+  <p class="incremental">
+    But there have been exceptions:
+  </p>
+  <ul class="incremental">
+    <li>
+      OpenVZ and VServer - mostly reimplemented with cgroups and
+      namespaces
+    </li>
+    <li>
+      Xen - now upstream; Linux 3.0 is a useful dom0 kernel!
+    </li>
+    <li>
+      aufs - needed for Debian Live
+    </li>
+    <li>
+      PREEMPT_RT - gradually being merged upstream; new option in
+      amd64 packages
+    </li>
+  </ul>
 </div>
 
 <div class="slide">
   <h1>Out-of-tree modules</h1>
+  <p>
+    The kernel team does not encourage the use of out-of-tree modules.
+    However, we support them by providing development packages and by
+    avoiding ABI changes during a stable release.
+  </p>
+  <p class="incremental">
+    Debian has two packages to aid in building out-of-tree modules:
+  </p>
+  <ul class="incremental">
+    <li>
+      <span class="package">dkms</span> - builds and installs modules
+      automatically.  Can build packages for installation on other
+      systems.  Also supported by Ubuntu and SUSE.
+    </li>
+    <li>
+      <span class="package">module-assistant</span> - builds packages
+      as directed.  Uses a separate package name for each kernel ABI.
+    </li>
+  </ul>
 </div>
 
 <div class="slide">
   <h1>Firmware files</h1>
+  <ul class="incremental">
+    <li>
+      Most peripherals have microcontroller running non-free
+      firmware; some require host to load it
+    </li>
+    <li>
+      Several drivers used to include firmware, making kernel
+      non-free.  Fudged with GRs for a while; finally fixed in squeeze
+    </li>
+    <li>
+      Users with these devices - almost any wifi card, some network
+      controllers and Radeon GPUs - will still need the firmware
+      files installed
+    </li>
+    <li>
+      Kernel team maintains
+      <span class="package">firmware-nonfree</span> source package
+      covering most firmware files that are clearly redistributable
+    </li>
+    <li>
+      Also collected in linux-firmware.git repository maintained by
+      David Woodhouse and myself
+    </li>
+  </ul>
 </div>
 
 <div class="slide">
   <h1>Documentation</h1>
+  <ul class="incremental">
+    <li>
+      <span class="package">manpages-dev</span> - the system call API
+    </li>
+    <li>
+      <span class="package">linux-doc-</span><var>upstream</var> -
+      miscellaneous upstream documentation
+    </li>
+    <li>
+      <span class="package">linux-manual-</span><var>upstream</var> -
+      the internal API, based on structured comments
+    </li>
+    <li>
+      <span class="package">debian-kernel-handbook</span> -
+      Debian-specific information; currently also Linux-specific but
+      could cover other kernels
+    </li>
+    <li>
+      <a href="http://wiki.debian.org/DebianKernel">http://wiki.debian.org/DebianKernel</a>
+      - wiki index page
+    </li>
+  </ul>
 </div>
 
 <div class="slide">
@@ -123,6 +453,38 @@
 <div class="slide">
   <h1>Credits</h1>
   <ul>
+    <li>
+      Linux 'Tux' logo &copy; Larry Ewing, Simon Budig.
+      <!--
+Redistribution is free but has to include this notice.
+      -->
+      <ul>
+	<li>Modified by me to add Debian open-ND logo</li>
+      </ul>
+    </li>
+    <li>
+      Debian open-ND logo &copy; Software in the Public Interest, Inc.
+      <!--
+Permission is hereby granted, free of charge, to any person obtaining
+a copy of this software and associated documentation files (the
+"Software"), to deal in the Software without restriction, including
+without limitation the rights to use, copy, modify, merge, publish,
+distribute, sublicense, and/or sell copies of the Software, and to
+permit persons to whom the Software is furnished to do so, subject to
+the following conditions:
+
+The above copyright notice and this permission notice shall be
+included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+      -->
+    </li>
     <li>
       DebConf 11 logo &copy; Aur&eacute;lio A. Heckert.
       <!--