# Talk:Unified Extensible Firmware Interface

## bcdedit

I do not think that the command

# bcdedit /set {bootmgr} path \EFI\path\to\app.efi


"tell the Windows boot loader to run a different UEFI application" as mentioned in the wiki (in the "Windows changes boot order" section) I think it add an entry in the UEFI firmware. But that can be as well accomplished under Linux with efibootmgr command. If the UEFI is weird (by refusing to boot something other than Windows for example); I do not think it will be of any help. I am not a Windows specialist and so I do not take the responsibility to edit this section, but someone more knowledgeable than me should double check it.

—This unsigned comment is by Olive (talk) 13:00, 20 September 2016‎. Please sign your posts with ~~~~!

From my reading, it seems that this command should trick windows into running a different EFI application instead of its own boot manager (bootmgfw.efi). I don't have the means to test it right now, but given that there are plenty of other recommendations in the article, I don't think it hurts to keep this command around. We'll just have to wait until someone gives it a test. Silverhammermba (talk) 15:35, 20 September 2016 (UTC)

## actually run the *.efi files on a PC

note: this is not per se a proposal to add something to the wiki, since that would require a plethora of "style tests" etc. which take years to perform. I just wanted to help out dudes with some quick info on a "talk" page, which used to be at core of a true, bona fide, wiki. Seems though, for every 10 lines of real wiki text, you get 15 lines of hostilities in return.

To actually run those *.efi files from AUR packages etc. :

use gnome-disk-utility / gnome-disks to format GPT-type table a USB3-thumbdrive. Create a partition of type BIOS-BOOT and one of type EFI-SYSTEM , format both as filesystem-type "FAT". This is done conveniently via GUI.

Then copy all files from the ARCHLinux install .iso image (mount it or sth.) onto those partitions. Add any *.efi you have - the apps from GNUefi (just unzip and make everything) work nicely. Create a boot-menu entry for KeyTool.efi by editing a .conf file appropriately. Now reboot your PC into that thumbdrive (choose via F10 , F8 or the suitable hotkey at boot-time).

KeyTool.efi ([screenshot]) has a nice menu to execute efi-binaries. Go back via ESC inside of the KeyTool.efi program to execute a different efi-file. You can also add / execute refind.efi which tells you whether SECURE mode is on or off - in case you don't want refind.efi on the hard-disk preinstalled.

This way you can e.g. sign some bootx64.efi or grubx64.efi . This is useful e.g. if some particular Firmware-BIOS is broken and will not allow you perform the signing, but break instead, e.g. with a garbled screen requiring RESET.

ls FS0: lists the files , use \ as subdir delimiter instead of /

F10 will save a screenshot onto the thumbdrive within rEFInd.efi

GNUefi apps like t7.c that wait for keypress before terminating can be launched right from the rEFInd GUI menu and will display screen-output.

rEFInd.efi is the new gujin ! If you have reset your BIOS to unclutter the BIOS-boot-menu, refind allows you to boot your disk again!

--UBF6 (talk) 06:57, 6 November 2018 (UTC)

This is described in the section Unified_Extensible_Firmware_Interface#UEFI_Bootable_Media and the linked page USB_flash_installation_media#BIOS_and_UEFI_bootable_USB. Phrases like "This takes just 60 seconds." don't belong on the wiki at all and talking about KeyTool.efi does not make sense without describing where it comes from and what it does. Second and third paragraphs are specific to your hardware/firmware. -- Lahwaacz (talk) 07:30, 6 November 2018 (UTC)
But that takes a long time to wade through a lot of text of dubious relevance. UBF6 (talk) 08:25, 6 November 2018 (UTC)
If you just want to launch other EFI applications, the simplest way to do it is from UEFI shell. The note in Unified Extensible Firmware Interface#Launching UEFI Shell explains how to boot the shell from a USB flash drive. KeyTool has a specific funtion, there's no need to use it just for launching EFI binaries. -- nl6720 (talk) 10:30, 6 November 2018 (UTC)
refind is simpler to use than UEFIshell to launch efi-apps. No need to learn \ or FS0: like in MS-DOS of 1980. UBF6 (talk) 12:43, 6 November 2018 (UTC)
If this is meant to be a proposal to add something to the wiki, please make it compatible with Help:Style#Language_register. Otherwise, if you want to write whatever you want using whatever language you like, you should start your own blog. -- Lahwaacz (talk) 18:10, 6 November 2018 (UTC)
This is a contribution in the style of a "cheat-sheet", doing away with long-winded verbiage. UBF6 (talk) 02:19, 7 November 2018 (UTC)

## Firmware bitness

I'm thinking of changing the Unified Extensible Firmware Interface#UEFI firmware bitness section. The current Non Macs and Apple Macs distinction is not very useful, I think it would be better to separate by the OS used in checking the bitness.

Plan:

• UEFI firmware bitness
• Checking the firmware bitness
• From Linux
• From Mac OS
• From Microsoft Windows (if I can find out how)

UEFI firmware bitness would contain generic information. Subsections of Checking the firmware bitness would contain OS-specific instructions on how to check the UEFI bitness from a running system.

-- nl6720 (talk) 10:12, 10 November 2018 (UTC)

Good enough for now. -- nl6720 (talk) 12:11, 17 November 2018 (UTC)