fuel-astute: Erase EFI boot entry on EFI systems

On EFI-enabled systemd, grub-install from grub-efi-* package
installs a boot entry named "ubuntu".

Since this boot entry is saved in board flash memory, erasing
the MBR bootloader code and/or partition signature will not
clear the ubuntu boot entry, leaving it pointing to a loader
on the ESP (EFI System Partition) that will try to load the
kernel/initrd from an erased partition.

In Fuel 8.0, the whole disk was erased, so the ubuntu EFI boot
entry was skipped due to missing ESP, while for Fuel 9.0 and
above we have to explicitly remove it to keep the system in a
sane state.

Note: efibootmgr is installed automatically on EFI systems
as a dependency of grub-efi-*.

Closes: ARMBAND-47

Change-Id: If715e960dfd96df807abb0e26f4b7604624ac408
Signed-off-by: Alexandru Avadanii <Alexandru.Avadanii@enea.com>

1 files changed, 43 insertions, 0 deletions

diff --git a/patches/fuel-astute/0001-Erase-EFI-boot-entry-on-EFI-systems.patch b/patches/fuel-astute/0001-Erase-EFI-boot-entry-on-EFI-systems.patch
new file mode 100644
index 00000000..905834df
--- /dev/null
+++ b/patches/fuel-astute/0001-Erase-EFI-boot-entry-on-EFI-systems.patch
@@ -0,0 +1,43 @@
+From: Alexandru Avadanii <Alexandru.Avadanii@enea.com>
+Date: Mon, 18 Jul 2016 16:02:20 +0200
+Subject: [PATCH] Erase EFI boot entry on EFI systems.
+
+On EFI-enabled systemd, grub-install from grub-efi-* package
+installs a boot entry named "ubuntu".
+
+Since this boot entry is saved in board flash memory, erasing
+the MBR bootloader code and/or partition signature will not
+clear the ubuntu boot entry, leaving it pointing to a loader
+on the ESP (EFI System Partition) that will try to load the
+kernel/initrd from an erased partition.
+
+In Fuel 8.0, the whole disk was erased, so the ubuntu EFI boot
+entry was skipped due to missing ESP, while for Fuel 9.0 and
+above we have to explicitly remove it to keep the system in a
+sane state.
+
+Note: efibootmgr is installed automatically on EFI systems
+as a dependency of grub-efi-*.
+
+Closes: ARMBAND-47
+
+Signed-off-by: Alexandru Avadanii <Alexandru.Avadanii@enea.com>
+---
+ mcagents/erase_node.rb | 4 ++++
+ 1 file changed, 4 insertions(+)
+
+diff --git a/mcagents/erase_node.rb b/mcagents/erase_node.rb
+index 3eb98e8..3bac36f 100644
+--- a/mcagents/erase_node.rb
++++ b/mcagents/erase_node.rb
+@@ -112,6 +112,10 @@ module MCollective
+         File.open('/proc/sys/kernel/panic','w') {|file| file.write("10\n")}
+ 
+         begin
++          # clear out EFI boot entry on EFI-enabled systems
++          system("(which efibootmgr > /dev/null 2>&1 && efibootmgr | "\
++                 "grep -oP '(?<=Boot)[0-9]+(?=.*ubuntu)' | "\
++                 "xargs -I{} efibootmgr --delete-bootnum --bootnum {}) || true")
+           get_devices(type='all').each do |dev|
+             debug_msg("erasing bootstrap code area in MBR of #{dev[:name]}")
+             # clear out the boot code in MBR