[PATCH 0/7] x86/efi: Prepwork for memory map cleanup

From: Ard Biesheuvel

Date: Fri Apr 10 2026 - 04:01:34 EST


From: Ard Biesheuvel <ardb@xxxxxxxxxx>

This is a follow-up to [0], which had some fundamental issues, as
spotted by Sashiko [1]. Disentangling the EFI memory map mess on x86
needs a rethink, but some of the prepwork is still worthwhile, and so it
is presented here separately.

The end goal is still the same, i.e., to remove the need for the x86
boot code to modify the EFI memory map, or reallocate/copy/remap it
numerous times.


[0] https://lore.kernel.org/all/20260319090529.1091660-21-ardb+git@xxxxxxxxxx/
[1] https://sashiko.dev/#/patchset/20260319090529.1091660-21-ardb%2Bgit%40google.com

Ard Biesheuvel (7):
x86/efi: Omit redundant kernel image overlap check
x86/efi: Drop redundant EFI_PARAVIRT check
x86/efi: Only merge EFI memory map entries on 32-bit systems
x86/efi: Defer sub-1M check from unmap to free stage
x86/efi: Simplify real mode trampoline allocation quirk
x86/efi: Unmap kernel-reserved boot regions from EFI page tables
x86/efi: Drop EFI_MEMORY_RUNTIME check from __ioremap_check_other()

arch/x86/include/asm/efi.h | 6 ++
arch/x86/mm/ioremap.c | 7 +-
arch/x86/platform/efi/efi.c | 39 +---------
arch/x86/platform/efi/efi_32.c | 31 ++++++++
arch/x86/platform/efi/quirks.c | 78 +++++++-------------
5 files changed, 69 insertions(+), 92 deletions(-)


base-commit: 259e3e6f9382b6a9fe570313d97c59a233f7d72f
--
2.53.0.1213.gd9a14994de-goog