Matt Gumbel of Intel has submitted a patch to the Linux-EFI and Linux-kernel lists, to add an EFI bootloader control driver to Linux:
efi: Introduce EFI bootloader control driver
This driver intercepts system reboot requests and populates the LoaderEntryOneShot EFI variable with the user-supplied reboot argument. EFI bootloaders such as Gummiboot will consume this variable and use it to control which OS is booted next. We use this with Android where reboot() tells the kernel that we want to boot into recovery or other non-default OS environment. It is the bootloader’s job to guard against this variable being uninitialzed or containing invalid data, and just boot normally if that is the case.
+config EFI_BOOTLOADER_CONTROL
+ tristate “EFI Bootloader Control module”
+ depends on EFI_VARS
+ default n
+ help
+ This driver installs a reboot hook, such that if reboot() is
+ invoked with a string argument NNN, “bootonce-NNN” is copied to
+ the EFI variable, to be read by the bootloader. If the string
+ matches one of the boot labels defined in its configuration,
+ the bootloader will boot once to that label.
For more information, see drivers/firmware/efi/efi-bc.c, the linux-efi or linux-kernel mailing lists:
http://vger.kernel.org/majordomo-info.html
Firmware Security 