1 (U)EFI boot loaders updater
2 ==========================
7 (U)EFI systems boot using boot loaders on a special EFI System Partition.
8 Many different boot loaders may be present at a time. These are not only
9 traditional boot loaders like GRUB, but arbitrary 'EFI applications'.
11 Xen or Linux kernel can be built as an EFI application too and booted directly
12 from the EFI firmware. The problem is the kernels and data or config files
13 needed for boot must be stored on the EFI System Partition, but that is not
14 the place where they are installed on package upgrade. And it is hard to
15 install files from RPM packages there directly.
17 efi-boot-update script makes it easy to manage the files on the EFI system
18 partition. Those files are to be installed in the regular Linux system and
19 will be copied to the EFI system partition using rules defined in
20 /etc/efi-boot/update.d/*.conf files (efi-boot-update modules).
22 efi-boot-update will also manage EFI boot manager configuration, adding
23 the configured boot loaders to the platform boot menu, provided the
24 'efibootmgr' package is installed and functional.
30 This is not another configuration interface for the boot loaders.
31 efi-boot-update can copy boot loader configuration files to the EFI system
32 partition, but it doesn't care about their contents or syntax.
37 When efi-boot-update is installed it should be automatically called whenever
38 any package containing EFI boot loader/application (or data for such
39 application) is installed, upgraded or removed.
41 The administrator may alter efi-boot-update operation editing the
42 global /etc/efi-boot/update.conf file and the efi-boot-update modules
43 in /etc/efi-boot/update.d (these configure rules for a specific application).
45 The administrator is also responsible to edit any configuration files used by
46 the boot loaders (usually in /etc/efi-boot).
48 efi-boot-update should be manually called whenever any of these files
51 /etc/efi-boot/update.conf
52 .........................
54 This file provide global settings for the efi-boot-update script. The
55 file uses POSIX shell syntax to set shell variables. Values containing
56 spaces should be quoted with double quotes.
58 Following variables can be set there:
60 * LABEL_PREFIX – the text to be prepended to every boot manager entry label
61 created by efi-boot-update.
62 * ORDER – preferred boot loader order. The value should contain
63 space-separated names of efi-boot-update modules in /etc/efi/update.d
64 (filenames there with '.conf' stripped).
65 * PLATFORM_DIR – subdirectory of the 'EFI' directory in the EFI system
66 partition where the EFI applications and data files will be stored.
67 The value may contain '@ARCH@', which will be replaced with the
68 architecture ('x64' or 'x32') for which the application was built (boot
69 loaders may have both 32-bit and 64-bit versions and it may be different
70 architecture that the one Linux is running).
72 modules in /etc/efi-boot/update.d
73 .................................
75 The *.conf files in the /etc/efi-boot/update.d directory provide rules for
76 installing a boot loader and creating the EFI boot manager label for it.
78 Following variables can be be set for each module:
80 * ENABLED – when 'yes', then the files will be copied and a boot manager
81 entry will be created for the application (provided BINARY is also set)
82 * LABEL – label to use for the boot manager entry (defaults to the module
84 * BINARY – name of the EFI binary installed in /boot/efi/EFI/$PLATFORM_DIR
85 or a path to any EFI binary existing on the EFI system partition
86 * ARGS – command line arguments for the EFI application
87 * ARCH – architecture the binary is built for
89 The module may define more configurable variables, but should use own unique
92 The module file should also contain a install_files() function definition
93 which defines what files are to be installed on the EFI system partition.
95 It can contain any shell code, but should not define any new global variables.
96 For convenience following are defined:
98 * '$DESTDIR' variable – defines the directory where the files should be
99 copied to that will be /boot/efi/EFI/$PLATFORM_DIR
100 * 'update_file' function – copies a file to the EFI partition
103 update_file [--missingok] SOURCE DEST
106 SOURCE – absolute path to the file to be copied
107 DEST – destination file name. Absolute (but should be in
108 /boot/efi) or, preferably, Relative to $DESTDIR
109 --missingok – when used, he command will not complain when the SOURCE
112 update_file behaviour depends on the '--verbose' and '--force' options
113 passed to the efi-boot-update script.
118 > efi-boot-update: EFI system partition not mounted.
120 To boot from EFI you need a GUID Partition Table on your HDD containing the
121 EFI system partition. And efi-boot-update needs the partition mounted at
124 When used with '--mount' option, efi-boot-update will try to find an mount the
125 partition, but for proper operation during package installation/upgrades the
126 partition should be always mounted.
128 > efi-boot-update: efibootmgr missing, won't update the boot manager
131 efi-boot-update needs the 'efibootmgr' utility to update the EFI boot manager
134 > efi-boot-update: efibootmgr does not work (efivars interface not available?)
135 > efi-boot-update: won't update boot manager configuration
137 The 'efibootmgr' does not always wark. It needs the 'efivars' kernel module
138 loaded (efi-boot-update takes care of that) and functioning correctly. This is
139 not always the case. The 'efivars' module works only when the kernel was
140 booted via EFI. If kernel has been started from from BIOS or is running
141 under Xen 'efibootmgr' won't work.
143 This causes a little boot strapping problem – you cannot use efi-boot-update
144 alone to configure system for the first UEFI boot.
146 efi-boot-update can still copy the files to the EFI partition, but one has
147 to manually select the boot loader via the EFI platform configuration