d/[..]/grub.d/xen.cfg: improve docs even more

Ok, I finally tried this, and it's really great that I now have correct
(different) linux kernel options generated for just linux and xen+dom0.

Do more cosmetics and reorganizing to make this wall of comments better
parseable by the eye. It was not obvious to me where sections started
and ended, and I like to have first the explanation and then at the end
the actual variables you can set.

Signed-off-by: Hans van Kranenburg <hans@knorrie.org>
Acked-by: Ian Jackson <ijackson@chiark.greenend.org.uk>

diff --git a/debian/tree/xen-hypervisor-common/etc/default/grub.d/xen.cfg b/debian/tree/xen-hypervisor-common/etc/default/grub.d/xen.cfg
index feb4be78e968f737d1bd1f18b5e87bea0efe1a66..a5559e10354cbac09c4e57a39c3d83ba06a1984a 100644 (file)
--- a/debian/tree/xen-hypervisor-common/etc/default/grub.d/xen.cfg
+++ b/debian/tree/xen-hypervisor-common/etc/default/grub.d/xen.cfg
@@ -1,20 +1,16 @@
-#
-# Uncomment the following variable and set to 0 or 1 to avoid warning.
-#
-#XEN_OVERRIDE_GRUB_DEFAULT=0
-
-echo "Including Xen overrides from /etc/default/grub.d/xen.cfg"
-
-#
 # When running update-grub with the Xen hypervisor installed, there are
 # some additional variables that can be used to pass options to the
 # hypervisor or the dom0 kernel.
-
-# The following two are used to generate arguments for the hypervisor:
 #
-#GRUB_CMDLINE_XEN_DEFAULT=""
-#GRUB_CMDLINE_XEN=""
+# The configuration in here makes it possible to have different options set
+# for the linux kernel when booting with or without Xen.
+
+echo "Including Xen overrides from /etc/default/grub.d/xen.cfg"
+
+#######################################################################
+# Xen Hypervisor Command Line Options
 #
+# The first two options are used to generate arguments for the hypervisor.
 # Commonly used options are:
 #
 # dom0_mem=<size>
@@ -43,16 +39,23 @@ echo "Including Xen overrides from /etc/default/grub.d/xen.cfg"
 #   code is ran inside, xpti for dom0 can be turned off for performance
 #   reasons. E.g. xpti=dom0=false,domu=true
 #
+# noreboot=true
+#   Do not automatically reboot after an error. This is useful for catching
+#   debug output.
+#
 # Please also refer to the "Xen Hypervisor Command Line Options"
 # documentation for the version of Xen you have installed. This
 # documentation can be found at https://xenbits.xen.org/
 #
-# The next two lines are used for creating kernel arguments for the dom0
-# kernel. This allows to have different options for the same kernel used
-# natively or as dom0 kernel.
+#GRUB_CMDLINE_XEN_DEFAULT=""
+#GRUB_CMDLINE_XEN=""
+
+#######################################################################
+# Dom0 Kernel Command Line Options
 #
-#GRUB_CMDLINE_LINUX_XEN_REPLACE_DEFAULT="$GRUB_CMDLINE_LINUX_DEFAULT"
-#GRUB_CMDLINE_LINUX_XEN_REPLACE="$GRUB_CMDLINE_LINUX"
+# The next options are used for creating kernel arguments for the dom0
+# kernel.  This allows to have different options for the same kernel used
+# natively or as dom0 kernel.
 #
 # For example:
 #
@@ -60,14 +63,18 @@ echo "Including Xen overrides from /etc/default/grub.d/xen.cfg"
 #   Allows to send early printk messages to the Xen hypervisor console
 #
 # console=hvc0
-#   Redirects the Linux console to the hypervisor console. When running
+#   Redirects the Linux console to the hypervisor console.  When running
 #   under Xen as dom0, this needs to be specified, because the usual ttyS0
 #   will not be available. When viewing the serial console, pressing Ctrl-A
 #   three times will switch between the Linux dom0 and the Xen Hypervisor.
+#
+#GRUB_CMDLINE_LINUX_XEN_REPLACE_DEFAULT="$GRUB_CMDLINE_LINUX_DEFAULT"
+#GRUB_CMDLINE_LINUX_XEN_REPLACE="$GRUB_CMDLINE_LINUX"
 
+# Make booting into Xen the default.  Set the following variable to 0 or 1
+# explicitly to avoid the message warning from being printed.
 #
-# Make booting into Xen the default if not changed above. Finding the
-# current string for it always has been a problem.
+#XEN_OVERRIDE_GRUB_DEFAULT=
 #
 if [ "$XEN_OVERRIDE_GRUB_DEFAULT" = "" ]; then
        echo "WARNING: GRUB_DEFAULT changed to boot into Xen by default!"