this post was submitted on 22 Aug 2024
548 points (98.8% liked)

Linux

48655 readers
647 users here now

From Wikipedia, the free encyclopedia

Linux is a family of open source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991 by Linus Torvalds. Linux is typically packaged in a Linux distribution (or distro for short).

Distributions include the Linux kernel and supporting system software and libraries, many of which are provided by the GNU Project. Many Linux distributions use the word "Linux" in their name, but the Free Software Foundation uses the name GNU/Linux to emphasize the importance of GNU software, causing some controversy.

Rules

Related Communities

Community icon by Alpár-Etele Méder, licensed under CC BY 3.0

founded 5 years ago
MODERATORS
you are viewing a single comment's thread
view the rest of the comments
[–] [email protected] 8 points 4 months ago (1 children)

EFI can also live in firmware memory.

You can pull the linux drive, boot from the windows drive, and if one of the firmware updates was for efi, windows will trash the entry for your Linux disk.

This has happened for me many times, I had to use a grub rescue disk to rebuild the efi table.

[–] [email protected] 1 points 3 months ago* (last edited 3 months ago) (1 children)

The boot entries live in firmware yes, efibootmgr can create and remove them. The are pointers to the bootloader. Many systems can boot from the disk itself without the entry, the entry just makes it pretty (“Fedora” instead of NVME1).

[–] [email protected] 1 points 3 months ago (1 children)

I'm not exactly sure what you're suggesting. Isn't that more or less what I just said?

[–] [email protected] 0 points 3 months ago* (last edited 3 months ago)

Somewhat. One, a system can be bootable without the entries because they are just pointers to the actual bootloader, so even if windows does the stupid and deletes them it isn’t the end of the world. It does depend on your specific firmware though.

Also two, you can write them again with a single line in efibootmgr, they’re just saying “if I click Fedora load the shim from the EFI system partition on disk 1”.

This is very different than the old world where windows would delete your bootloader entirely and the MBR couldn’t be easily explored. They live in the efi system partition instead - or at least the shim does- and typically every OS leaves the other ones alone (even Windows, except in this case, although it didn’t touch the shim itself).

The initial comment was about the bootloader and really only applies to MBR partitions.