Trade-offs

Posted Oct 10, 2025 5:48 UTC (Fri) by mjg59 (subscriber, #23239)
In reply to: Trade-offs by mb
Parent article: Last-minute /boot boost for Fedora 43

UEFI doesn't really have a good concept of multiple displays and tends to make sub-optimal compromises if you have several active displays plugged in, so aesthetically there's a significant benefit to having a proper driver running

Trade-offs

Posted Oct 10, 2025 6:05 UTC (Fri) by mb (subscriber, #50428) [Link] (3 responses)

Why would I need multiple displays to enter a password?

Trade-offs

Posted Oct 10, 2025 6:07 UTC (Fri) by vasi (subscriber, #83946) [Link]

I imagine if you have a system that usually has three displays attached, you don't want to unplug two of them just so the UEFI can ask you for a password.

Trade-offs

Posted Oct 10, 2025 6:13 UTC (Fri) by mjg59 (subscriber, #23239) [Link]

You don't, it's just that it looks much nicer if the display you're looking at is actually in native resolution when prompting you (UEFI has no way to know which of the displays you have attached is the one you actually care about at that point)

Trade-offs

Posted Oct 10, 2025 6:59 UTC (Fri) by josh (subscriber, #17465) [Link]

It would be nice to, for instance, prompt on the external monitor you have plugged in, rather than the closed laptop screen. (Yes, I've seen laptops whose firmware graphics has this problem.)

Trade-offs

Posted Oct 10, 2025 6:16 UTC (Fri) by vasi (subscriber, #83946) [Link]

Oh "fun"! That is a good reason.

Though this is starting to feel like we'll eventually need an extra stage of loading Linux. Eg:

Stage 1: Get to a bootloader. (Obviously there's earlier steps, but let's start here.)
Stage 2: Load Linux and initrd into memory. We need just enough in initrd to access some real storage in early userland.
Stage 3: Initrd loads further modules from storage, for things like LUKS passwords. Eventually loads root fs and boots to full userland.

Our forced-memory-resident initrd could be much smaller. Our big stage3 modules could live anywhere that Linux supports, instead of being reliant on the minimal filesystem drivers in bootloaders.

Trade-offs

Posted Oct 10, 2025 8:24 UTC (Fri) by farnz (subscriber, #17727) [Link]

Out of interest, how does Windows handle it when it needs a Bitlocker recovery key?

I can see online that it prompts you for it via a GUI screen, but I'm not clear on whether it uses UEFI graphics, or whether it's able to load enough Windows kernel bits to run the hardware-native display driver at this point.

Put differently, are we trying to be better than Windows on the same hardware (a worthy goal, but one that can perhaps be deferred a bit), or is this a case where not using the native display driver makes us clearly worse than Windows on a given machine (where we need to be equal or clearly better to be a competitive alternative)?