Merge remote-tracking branch 'origin/trunk' into xry111/arm64

3 files changed, 49 insertions, 36 deletions

diff --git a/chapter07/creatingdirs.xml b/chapter07/creatingdirs.xml
index bc6162e61..35a0a9003 100644
--- a/chapter07/creatingdirs.xml
+++ b/chapter07/creatingdirs.xml
@@ -10,10 +10,10 @@
 
   <title>Creating Directories</title>
 
-  <para>It is time to create the full structure in the LFS file system.</para>
+  <para>It is time to create the full directory structure in the LFS file system.</para>
 
-  <note><para>Some of the directories mentioned in this section may be
-  already created earlier with explicit instructions or when installing some
+  <note><para>Some of the directories mentioned in this section may have
+  already been created earlier with explicit instructions, or when installing some
   packages.  They are repeated below for completeness.</para></note>
 
   <para>Create some root-level directories that are not in the limited set
@@ -42,14 +42,14 @@ install -dv -m 0750 /root
 install -dv -m 1777 /tmp /var/tmp</userinput></screen>
 
   <para>Directories are, by default, created with permission mode 755, but
-  this is not desirable for all directories. In the commands above, two
+  this is not desirable everywhere. In the commands above, two
   changes are made&mdash;one to the home directory of user <systemitem
   class="username">root</systemitem>, and another to the directories for
   temporary files.</para>
 
   <para>The first mode change ensures that not just anybody can enter
-  the <filename class="directory">/root</filename> directory&mdash;the
-  same as a normal user would do with his or her home directory. The
+  the <filename class="directory">/root</filename> directory&mdash;just
+  like a normal user would do with his or her own home directory. The
   second mode change makes sure that any user can write to the
   <filename class="directory">/tmp</filename> and <filename
   class="directory">/var/tmp</filename> directories, but cannot remove
@@ -59,14 +59,14 @@ install -dv -m 1777 /tmp /var/tmp</userinput></screen>
   <sect2>
     <title>FHS Compliance Note</title>
 
-    <para>The directory tree is based on the Filesystem Hierarchy Standard
+    <para>This directory tree is based on the Filesystem Hierarchy Standard
     (FHS) (available at <ulink
     url="https://refspecs.linuxfoundation.org/fhs.shtml"/>).  The FHS also specifies
-    the optional existence of some directories such as <filename
+    the optional existence of additional directories such as <filename
     class="directory">/usr/local/games</filename> and <filename
-    class="directory">/usr/share/games</filename>.  We create only the
-    directories that are needed. However, feel free to create these
-    directories.  </para>
+    class="directory">/usr/share/games</filename>.  In LFS, we create only the
+    directories that are really necessary. However, feel free to create more
+    directories, if you wish.  </para>
 
   </sect2>
 
diff --git a/chapter07/introduction.xml b/chapter07/introduction.xml
index 6605ddea4..d00f3fe2a 100644
--- a/chapter07/introduction.xml
+++ b/chapter07/introduction.xml
@@ -11,22 +11,22 @@
   <title>Introduction</title>
 
   <para>This chapter shows how to build the last missing bits of the temporary
-  system: the tools needed by the build machinery of various packages.  Now
+  system: the tools needed to build the various packages.  Now
   that all circular dependencies have been resolved, a <quote>chroot</quote>
   environment, completely isolated from the host operating system (except for
   the running kernel), can be used for the build.</para>
 
   <para>For proper operation of the isolated environment, some communication
-  with the running kernel must be established. This is done through the
-  so-called <emphasis>Virtual Kernel File Systems</emphasis>, which must be
-  mounted when entering the chroot environment. You may want to check
-  that they are mounted by issuing <command>findmnt</command>.</para>
+  with the running kernel must be established. This is done via the
+  so-called <emphasis>Virtual Kernel File Systems</emphasis>, which will be
+  mounted before entering the chroot environment. You may want to verify
+  that they are mounted by issuing the <command>findmnt</command> command.</para>
 
   <para>Until <xref linkend="ch-tools-chroot"/>, the commands must be
   run as <systemitem class="username">root</systemitem>, with the
   <envar>LFS</envar> variable set. After entering chroot, all commands
   are run as &root;, fortunately without access to the OS of the computer
   you built LFS on. Be careful anyway, as it is easy to destroy the whole
-  LFS system with badly formed commands.</para>
+  LFS system with bad commands.</para>
 
 </sect1>
diff --git a/chapter07/kernfs.xml b/chapter07/kernfs.xml
index c9721113d..3e96bee5e 100644
--- a/chapter07/kernfs.xml
+++ b/chapter07/kernfs.xml
@@ -14,12 +14,14 @@
     <primary sortas="e-/dev/">/dev/*</primary>
   </indexterm>
 
-    <para>Various file systems exported by the kernel are used to communicate to
-    and from the kernel itself. These file systems are virtual in that no disk
+    <para>Applications running in user space utilize various file 
+    systems exported by the kernel to communicate 
+    with the kernel itself. These file systems are virtual: no disk
     space is used for them. The content of the file systems resides in
-    memory.</para>
+    memory. These file systems must be mounted in the $LFS directory tree
+    so the applications can find them in the chroot environment.</para>
 
-    <para>Begin by creating directories onto which the file systems will be
+    <para>Begin by creating directories on which the file systems will be
     mounted:</para>
 
 <screen><userinput>mkdir -pv $LFS/{dev,proc,sys,run}</userinput></screen>
@@ -27,20 +29,31 @@
   <sect2 id="ch-tools-bindmount">
     <title>Mounting and Populating /dev</title>
 
-      <para>During a normal boot, the kernel automatically mounts the
-      <systemitem class="filesystem">devtmpfs</systemitem> filesystem on the
-      <filename class="directory">/dev</filename> directory, and allow the
-      devices to be created dynamically on that virtual filesystem as they
-      are detected or accessed. Device creation is generally done during the
-      boot process by the kernel and Udev.
-      Since this new system does not yet have Udev and
-      has not yet been booted, it is necessary to mount and populate
-      <filename class="directory">/dev</filename> manually. This is
-      accomplished by bind mounting the host system's
+      <para>During a normal boot of the LFS system, the kernel automatically
+      mounts the <systemitem class="filesystem">devtmpfs</systemitem>
+      filesystem on the
+      <filename class="directory">/dev</filename> directory; the kernel
+      creates device nodes on that virtual filesystem during the boot process
+      or when a device is first detected or accessed. The udev daemon may
+      change the owner or permission of the device nodes created by the
+      kernel, or create new device nodes or symlinks to ease the work of
+      distro maintainers or system administrators.  (See
+      <xref linkend='ch-config-udev-device-node-creation'/> for details.)
+      If the host kernel supports &devtmpfs;, we can simply mount a
+      &devtmpfs; at <filename class='directory'>$LFS/dev</filename> and rely
+      on the kernel to populate it (the LFS building process does not need
+      the additional work onto &devtmpfs; by udev daemon).</para>
+
+      <para>But, some host kernels may lack &devtmpfs; support and these
+      host distros maintain the content of
+      <filename class="directory">/dev</filename> with different methods.
+      So the only host-agnostic way for populating
+      <filename class="directory">$LFS/dev</filename> is
+      bind mounting the host system's
       <filename class="directory">/dev</filename> directory. A bind mount is
       a special type of mount that allows you to create a mirror of a
-      directory or mount point to some other location. Use the following
-      command to achieve this:</para>
+      directory or mount point at some other location. Use the following
+      command to do this:</para>
 
 <screen><userinput>mount -v --bind /dev $LFS/dev</userinput></screen>
 
@@ -89,10 +102,10 @@ mount -vt tmpfs tmpfs $LFS/run</userinput></screen>
       The /run tmpfs was mounted above so in this case only a
       directory needs to be created.</para>
 
-      <para>In other cases <filename>/dev/shm</filename> is a mountpoint 
+      <para>In other host systems <filename>/dev/shm</filename> is a mount point 
       for a tmpfs. In that case the mount of /dev above will only create
-      /dev/shm in the chroot environment as a directory. In this situation
-      we explicitly mount a tmpfs,</para>
+      /dev/shm as a directory in the chroot environment. In this situation
+      we must explicitly mount a tmpfs:</para>
 
 <screen><userinput>if [ -h $LFS/dev/shm ]; then
   mkdir -pv $LFS/$(readlink $LFS/dev/shm)