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= BiggerESP

This is a proposed Change for Fedora Linux.
This document represents a proposed Change. As part of the Changes process, proposals are publicly announced in order to receive community feedback. This proposal will only be implemented if approved by the Fedora Engineering Steering Committee.

Summary

The Fedora installer includes an EFI System Partition of between 200MB and 600MB by default, of which the lower size is much too small for firmware updates on modern hardware and also for future bootloader features like UKI. This change will increase the minimum size of the ESP to be 500MB, which is also the same value used by Microsoft for Windows 10 and newer.

Owner

Current status

  • Targeted release: Fedora Linux 39
  • Last updated: 2023-04-24
  • FESCo issue: <will be assigned by the Wrangler>
  • Tracker bug: <will be assigned by the Wrangler>
  • Release notes tracker: <will be assigned by the Wrangler>

Detailed Description

Modern hardware has UEFI firmware updates that are more than 64MB in size. The OEMs recommend a ESP free space of double the flash size plus 20MB and fwupd now enforces this requirement to ensure flash success. As the ESP is often shared between Windows and Linux, and also used for firmware updates, and soon to be used by UKIs it's not enough to just allocate a few hundreds of megabytes. Windows 10 and 11 allocates an ESP of at least 500MiB. Arch also specifies a minimum of 512 MiB.

Feedback

There is no alternative -- the ESP has to scale up if we want firmware updates to continue to work and to support UKIs for next-generation bootloaders.

Benefit to Fedora

Firmware updates will work on future hardware, and we can boot the kernel using UKIs using next-generation bootloaders.

Scope

  • Proposal owners:

We need to change a number in Anaconda: https://github.com/rhinstaller/anaconda/pull/4711

Upgrade/compatibility impact

We can't grow the ESP in size, and so this change will only affect new installs. This is fine, as this will affect new hardware more than old hardware.

How To Test

Install Fedora and observe that /boot/efi has at least 276MB free space, even when installed alongside Windows.

Dependencies

Anaconda would need to be modified, and Fedora would have a / or /home partition that's ~300MB smaller by default than it is now.

Contingency Plan

  • Contingency mechanism: (What to do? Who will do it?) N/A (not a System Wide Change)
  • Contingency deadline: N/A (not a System Wide Change)
  • Blocks release? N/A (not a System Wide Change), No

Documentation

N/A (not a System Wide Change)

Release Notes

Fedora now defaults to a larger EFI System Partition which allows firmware updates to work on newer hardware, and allows future bootloader and kernel modernizations.