X-Git-Url: https://git.decadent.org.uk/gitweb/?a=blobdiff_plain;ds=sidebyside;f=index.html;h=460eddfff88e201004107902c055cc6f3b52e7d5;hb=13946897fa8776bdc6eda8847cb6847d53e42594;hp=59e50ca9057f4fec58c597d85a58004e2153353d;hpb=333c89647d2bb479541eb707117284ab060e0a6f;p=i-t-talk.git

diff --git a/index.html b/index.html
index 59e50ca..460eddf 100644
--- a/index.html
+++ b/index.html
@@ -72,8 +72,90 @@
       it can't read them from the root filesystem
     </li>
     <li>
-      Solution: boot loader provides a bundle of files to the
-      kernel
+      Solution: boot loader provides a bundle of files
+      (initramfs image) to the kernel
+    </li>
+  </ul>
+</div>
+
+<div class="slide">
+  <img src="yo-dawg.jpeg" width="90%" />
+</div>
+
+<div class="slide">
+  <h1>How the kernel uses an initramfs</h1>
+  <ul class="incremental">
+    <li>
+      Kernel <em>always</em> mounts an initial root filesystem using
+      either ramfs or tmpfs
+    </li>
+    <li>
+      If the boot loader provides an initramfs image, kernel
+      unpacks it into this filesystem, then runs <tt>/init</tt>
+    </li>
+    <li>
+      The initramfs init system is then responsible for mounting
+      the real root filesystem and running the real <tt>init</tt>
+      <ul class="incremental">
+	<li>
+	  Although it is not <em>required</em> to hand over at all
+	  - e.g. debian-installer
+	</li>
+      </ul>
+    </li>
+  </ul>
+</div>
+
+<div class="slide">
+  <h1>Overview</h1>
+  <ul class="incremental">
+    <li>
+      Started in Ubuntu in 2005 and adopted in Debian later that year
+    </li>
+    <li>
+      <tt>mkinitramfs</tt> builds an initramfs image using the
+      included scripts, necessary kernel modules, udev, and utilities
+      from klibc-utils or busybox
+    </li>
+    <li>
+      Uses build-time and boot-time hook scripts for
+      extensibility
+      <ul>
+	<li>Used by btrfs-tools, cryptsetup, lvm2, mdadm, etc.</li>
+      </ul>
+    </li>
+    <li>
+      Supports dependencies within each set of scripts
+    </li>
+  </ul>
+</div>
+
+<div class="slide">
+  <h1>The init system</h1>
+  <ul class="incremental">
+    <li>
+      Mount <tt>devtmpfs</tt>, <tt>devpts</tt>, <tt>procfs</tt>,
+      <tt>sysfs</tt>, <tt>tmpfs</tt> at <tt>/run</tt>
+    </li>
+    <li>
+      Run <tt>init-top</tt> scripts - includes starting udev
+    </li>
+    <li>
+      Load explicitly configured modules
+    </li>
+    <li>
+      Run <tt>init-premount</tt> scripts
+    </li>
+    <li>
+      Run <tt>local-top</tt> or <tt>nfs-top</tt> scripts
+      - e.g. mdadm setup
+    </li>
+    <li>
+      Run <tt>local-premount</tt> or <tt>nfs-premount</tt> scripts
+      - e.g. btrfs scan, resume from disk
+    </li>
+    <li>
+      Mount root filesystem
     </li>
   </ul>
 </div>
@@ -117,6 +199,9 @@ 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>
+      Xzibit promotional photo &copy; Retna, used for purpose of parody
+    </li>
   </ul>
 </div>