Provide a script to generate VM kernel files

kernel-modules/Makefile

@@ -1,7 +1,11 @@
 ver		:= $(shell cat ../version)
 srcdir	:= /usr/src/u2mfn-$(ver)
 
-install:	install-u2mfn
+install:	install-u2mfn install-scripts
+
+install-scripts:
+	install -d $(DESTDIR)/usr/sbin
+	install qubes-prepare-vm-kernel $(DESTDIR)/usr/sbin
 
 install-u2mfn:
 	install -d $(DESTDIR)$(srcdir)

kernel-modules/qubes-prepare-vm-kernel

@@ -0,0 +1,87 @@
+#!/bin/sh
+#
+# The Qubes OS Project, http://www.qubes-os.org
+#
+# Copyright (C) 2015  Marek Marczykowski-Górecki
+#                       <marmarekp@invisiblethingslab.com>
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+#
+#
+
+set -e
+
+basedir=/var/lib/qubes/vm-kernels
+
+function recompile_u2mfn() {
+    kver=$1
+    u2mfn_ver=`dkms status u2mfn|tail -n 1|cut -f 2 -d ' '|tr -d ':,'`
+    dkms install u2mfn/$u2mfn_ver -k $kver
+}
+
+function build_modules_img() {
+    kver=$1
+    output_file=$2
+
+    mkdir /tmp/qubes-modules-$kver
+    truncate -s 400M /tmp/qubes-modules-$kver.img
+    mkfs -t ext3 -F /tmp/qubes-modules-$kver.img > /dev/null
+    mount /tmp/qubes-modules-$kver.img /tmp/qubes-modules-$kver -o loop
+    cp -a -t /tmp/qubes-modules-$kver /lib/modules/$kver
+    umount /tmp/qubes-modules-$kver
+    rmdir /tmp/qubes-modules-$kver
+    mv /tmp/qubes-modules-$kver.img $output_file
+}
+
+function build_initramfs() {
+    kver=$1
+    output_file=$2
+
+    /sbin/dracut --nomdadmconf --nolvmconf --force \
+        --modules "bash dm kernel-modules rootfs-block base fs-lib shutdown" \
+        --modules "qubes-vm" --conf /dev/null --confdir /var/empty \
+        -d "xenblk xen-blkfront cdrom ext4 jbd2 crc16 dm_snapshot" \
+        $output_file $kver
+}
+
+if [ -z "$1" ]; then
+    echo "Usage: $0 <kernel-version> [<display-kernel-version>]" >&2
+    exit 1
+fi
+
+if [ ! -r /boot/vmlinuz-$1 -o ! -d /lib/modules/$1 ]; then
+    echo "ERROR: Kernel version $1 not installed" >&2
+    exit 1
+fi
+
+kernel_version=$1
+if [ -n "$2" ]; then
+    output_dir="$basedir/$2"
+else
+    output_dir="$basedir/$kernel_version"
+fi
+
+echo "--> Building files for $kernel_version in $output_dir"
+
+echo "---> Recompiling kernel module (u2mfn)"
+recompile_u2mfn "$kernel_version"
+mkdir -p "$output_dir"
+cp "/boot/vmlinuz-$kernel_version" "$output_dir/vmlinuz"
+echo "---> Generating modules.img"
+build_modules_img "$kernel_version" "$output_dir/modules.img"
+echo "---> Generating initramfs"
+build_initramfs "$kernel_version" "$output_dir/initramfs"
+
+echo "--> Done."

rpm_spec/qubes-kernel-vm-support.spec

@@ -61,6 +61,7 @@ make install-kernel-support DESTDIR=%{buildroot}
 %files
 /usr/lib/dracut/modules.d/90qubes-vm
 /usr/src/u2mfn-%{version}/
+/usr/sbin/qubes-prepare-vm-kernel
 
 %post
 dkms add -m u2mfn -v %{version} --rpm_safe_upgrade