[PATCH V3 0/1] kernel-grub.bbclass: add a method to install/update for bzImage

[PATCH V3 0/1] kernel-grub.bbclass: add a method to install/update for bzImage

[Hongxu Jia]

Change in V3:
 - Don't check for '$D' to be empty to support cross-install/cross-upgrade
   situation;
 - Use $grubcfg instead of hardcoded '/boot/grub/*';

Change in V2: Create a "kernel-grub.bbclass" to do the job which means
              it is disabled by default.

Test Case:
1. Add INHERIT_append = " kernel-grub" to local.conf and build a new kernel
   image rpm package.

2. Prepare a deployed target, and make sure your boot area has enough disk
   space (free space >= 5MB).

3. Download the new kernel image rpm to the target.

4. Before install/update, check boot area and menu
root@qemux86-64:~# ls /boot/
grub        vmlinuz

root@qemux86-64:~# cat /boot/grub/grub.cfg
menuentry "Linux" {
    set root=(hd0,1)
    linux /vmlinuz root=/dev/hdb2  rw  console=tty0  quiet
}

4. Install/update bzImage
root@qemux86-64:~# rpm -i kernel-image-3.10.11-yocto-standard-3.10.12+git0+285f93bf94_702040ac7c-r0.qemux86_64.rpm 
Caution! Update kernel may affect kernel-module!
update-alternatives: Linking //boot/bzImage to bzImage-3.10.11-yocto-standard

5. After install/update, check boot area and menu
root@qemux86-64:~# ls /boot/ -al
drwxr-xr-x    4 root     root          1024 Sep 18 06:58 .
drwxr-xr-x   17 root     root          4096 Sep 18 06:41 ..
lrwxrwxrwx    1 root     root            30 Sep 18 06:58 bzImage -> bzImage-3.10.11-yocto-standard
-rw-r--r--    1 root     root       5601808 Sep 18 06:45 bzImage-3.10.11-yocto-standard
drwxr-xr-x    4 root     root          1024 Sep 18 06:58 grub
-rwxr-x---    1 root     root       5601776 Sep 18 06:38 vmlinuz

root@qemux86-64:~# cat /boot/grub/grub.cfg 
menuentry "Update bzImage-3.10.11-yocto-standard-3.10.12+gitAUTOINC+285f93bf94_702040ac7c" {
    set root=(hd0,1)
    linux /bzImage-3.10.11-yocto-standard root=/dev/hdb2  rw  console=tty0  quiet
}
menuentry "Linux" {
    set root=(hd0,1)
    linux /vmlinuz root=/dev/hdb2  rw  console=tty0  quiet
}


6. Reboot target, 'Update bzImage-3.10.11-yocto-standard-3.10.12+gitAUTOINC+285f93bf94_702040ac7c'
   will be in the boot menu.

7. It supports GRUB 0.97 in which use menu.lst rather than grub.cfg as config
   file.

8. If you install the same rpm more than one time with '--force', there will
   be multiple kernel images in boot area and menu.

9. It works for dep and ipk.

//Hongxu

The following changes since commit 529bf977e956175bd8405ebffc88194192e44740:

  update-rcd.bbclass: fix host/target test (2013-10-16 14:51:07 +0100)

are available in the git repository at:

  git://git.pokylinux.org/poky-contrib hongxu/update-bzimage
  http://git.pokylinux.org/cgit.cgi/poky-contrib/log/?h=hongxu/update-bzimage

Hongxu Jia (1):
  kernel-grub.bbclass: add a method to install/update for bzImage

 meta/classes/kernel-grub.bbclass | 90 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 90 insertions(+)
 create mode 100644 meta/classes/kernel-grub.bbclass

-- 
1.8.1.2

[PATCH 1/1] kernel-grub.bbclass: add a method to install/update for bzImage

[Hongxu Jia]

While installing a rpm to update kernel on a deployed target, it will update
the boot area and the boot menu with the kernel as the priority but allow
you to fall back to the original kernel as well.

- In kernel-image's preinstall scriptlet, it backs up original kernel to avoid
  probable confliction with the new one.
- In kernel-image's postinstall scriptlet, it modify grub's config file to
  updates the new kernel as the boot priority.

[YOCTO #4104]

Signed-off-by: Hongxu Jia <hongxu.jia@windriver.com>
---
 meta/classes/kernel-grub.bbclass | 90 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 90 insertions(+)
 create mode 100644 meta/classes/kernel-grub.bbclass

diff --git a/meta/classes/kernel-grub.bbclass b/meta/classes/kernel-grub.bbclass
new file mode 100644
index 0000000..70564f0
--- /dev/null
+++ b/meta/classes/kernel-grub.bbclass
@@ -0,0 +1,90 @@
+#
+# While installing a rpm to update kernel on a deployed target, it will update
+# the boot area and the boot menu with the kernel as the priority but allow
+# you to fall back to the original kernel as well.
+#
+# - In kernel-image's preinstall scriptlet, it backs up original kernel to avoid
+#   probable confliction with the new one.
+#
+# - In kernel-image's postinstall scriptlet, it modifies grub's config file to
+#   updates the new kernel as the boot priority.
+#
+
+pkg_preinst_kernel-image_append () {
+	# Parsing confliction
+	[ -f "$D/boot/grub/menu.list" ] && grubcfg="$D/boot/grub/menu.list"
+	[ -f "$D/boot/grub/grub.cfg" ] && grubcfg="$D/boot/grub/grub.cfg"
+	if [ -n "$grubcfg" ]; then
+		# Dereference symlink to avoid confliction with new kernel name.
+		if grep -q "/${KERNEL_IMAGETYPE} \+root=" $grubcfg; then
+			if [ -L "$D/boot/${KERNEL_IMAGETYPE}" ]; then
+				kimage=`realpath $D/boot/${KERNEL_IMAGETYPE} 2>/dev/null`
+				if [ -f "$D$kimage" ]; then
+					sed -i "s:${KERNEL_IMAGETYPE} \+root=:${kimage##*/} root=:" $grubcfg
+				fi
+			fi
+		fi
+
+		# Rename old kernel if it conflicts with new kernel name.
+		if grep -q "/${KERNEL_IMAGETYPE}-${KERNEL_VERSION} \+root=" $grubcfg; then
+			if [ -f "$D/boot/${KERNEL_IMAGETYPE}-${KERNEL_VERSION}" ]; then
+				timestamp=`date +%s`
+				kimage="$D/boot/${KERNEL_IMAGETYPE}-${KERNEL_VERSION}-$timestamp-back"
+				sed -i "s:${KERNEL_IMAGETYPE}-${KERNEL_VERSION} \+root=:${kimage##*/} root=:" $grubcfg
+				mv "$D/boot/${KERNEL_IMAGETYPE}-${KERNEL_VERSION}" "$kimage"
+			fi
+		fi
+	fi
+}
+
+pkg_postinst_kernel-image_prepend () {
+	get_new_grub_cfg() {
+		grubcfg="$1"
+		title="Update ${KERNEL_IMAGETYPE}-${KERNEL_VERSION}-${PV}"
+		if [ "${grubcfg##*/}" = "grub.cfg" ]; then
+			rootfs=`grep " *linux \+[^ ]\+ \+root=" $grubcfg -m 1 | \
+				 sed "s# *linux \+[^ ]\+ \+root=#    linux /${KERNEL_IMAGETYPE}-${KERNEL_VERSION} root=#"`
+
+			echo "menuentry \"$title\" {"
+			echo "    set root=(hd0,1)"
+			echo "$rootfs"
+			echo "}"
+		elif [ "${grubcfg##*/}" = "menu.list" ]; then
+			rootfs=`grep "kernel \+[^ ]\+ \+root=" $grubcfg -m 1 | \
+				 sed "s#kernel \+[^ ]\+ \+root=#kernel /${KERNEL_IMAGETYPE}-${KERNEL_VERSION} root=#"`
+
+			echo "default 0"
+			echo "timeout 30"
+			echo "title $title"
+			echo "root  (hd0,0)"
+			echo "$rootfs"
+		fi
+	}
+
+	get_old_grub_cfg() {
+		grubcfg="$1"
+		if [ "${grubcfg##*/}" = "grub.cfg" ]; then
+			cat "$grubcfg"
+		elif [ "${grubcfg##*/}" = "menu.list" ]; then
+			cat "$grubcfg" | sed -e '/^default/d' -e '/^timeout/d'
+		fi
+	}
+
+	if [ -f "$D/boot/grub/grub.cfg" ]; then
+		grubcfg="$D/boot/grub/grub.cfg"
+		old_image=`grep ' *linux \+[^ ]\+ \+root=' -m 1 "$grubcfg" | awk '{print $2}'`
+	elif [ -f "$D/boot/grub/menu.list" ]; then
+		grubcfg="$D/boot/grub/menu.list"
+		old_image=`grep '^kernel \+[^ ]\+ \+root=' -m 1 "$grubcfg" | awk '{print $2}'`
+	fi
+
+	# Don't update grubcfg at first install while old bzImage doesn't exist.
+	if [ -f "$D/boot/$old_image" ]; then
+		grubcfgtmp="$grubcfg.tmp"
+		get_new_grub_cfg "$grubcfg"  > $grubcfgtmp
+		get_old_grub_cfg "$grubcfg" >> $grubcfgtmp
+		mv $grubcfgtmp $grubcfg
+		echo "Caution! Update kernel may affect kernel-module!"
+	fi
+}
+
-- 
1.8.1.2