Linux UEFI boot on Lenovo m91p

gistfile1.txt

# http://www.rodsbooks.com/linux-uefi/
# 1. Install Linux normally 
# 2. Boot from Linux live usb drive
# 3. Most likely /dev/sda1 but it can be something else:
mount /dev/sda1 /mnt
mkdir -p /mnt/EFI/Microsoft/Boot
# 5. Depending on if it is ubuntu, centos or any other distro:
cp /mnt/EFI/centos/grubx64.efi /mnt/EFI/Microsoft/Boot/bootmgfw.efi
# I don't remember but I think it was like this.
7 efibootmgr --create --label "Windows Boot Manager" --loader "\EFI\Microsoft\Boot\bootmgfw.efi"

Today, I posted the following instructions at https://gist.github.com/vees/b3fb1e5b62da155a006831c16eaac8e8#gistcomment-4594603

Note that is not needed to create a Microsoft directory.

I hope this help.

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I am doing some tests around a Lenovo ThinkCentre M91p with Windows 10 / Debian 12 (Bookworm) to write a specific technical document about EFI boot.

Considering a dual boot, I installed Windows and, after this, Debian. The machine stopped to start, showing the error "1962: No operating system found". Thus, I did the boot using a flash drive with "Ventoy"[1] and rEFInd[2] on Ventoy (is needed to write the Ventoy ISO to the flash drive using dd or dcfldd and the ISO image of rEFind inside of Ventoy partition). rEFInd is able to read the \EFI partition and to boot any system found there. I booted the Debian.

[1] https://www.ventoy.net/en/download.html
[2] https://sourceforge.net/projects/refind/

On Debian, I set a label for the Debian/GRUB as "Windows Boot Manager" (Lenovo M91p always searches for this label) and I set the boot order to Debian only. On Debian I also made an update-grub to add the Windows to GRUB. My Debian is set as Boot0001 (the command # efibootmgr will show this information), so Debian = 0001. The following commands were used:

• To remove the current Debian entry (see # efibootmgr -v):

# efibootmgr -b 0001 -B

• To rewrite the Debian entry:

# efibootmgr -c -d /dev/sda -p 1 -l '\EFI\debian\grubx64.efi' -L "Windows Boot Manager"

• To set 0001 as the main system in the BootOrder field.

# efibootmgr -o 0001

• To test:

# reboot

A simple command reference: https://www.linuxbabe.com/command-line/how-to-use-linux-efibootmgr-examples

Enjoy!