[SRU][Q][PATCH 0/1] Questing fails to boot on (older) Macs (LP: #2105402)

[Kevin Becker]

BugLink: https://bugs.launchpad.net/bugs/2105402

[Impact]

MacBookAir7,1 (i5-5250U)
MacBookPro12,1 (i5-5287U)
iMac14,1 (i5-4570R)

With three older Macs, Questing fails to boot.

The built-in displays stay blank but the backlight is visible until I force the computers to power off. External video doesn't show anything.

I have tried both installed (more below) and live images. With the live image the GRUB menu with "Try or install" does show up.

All three do boot normally to 24.10 live images. The iMac has 24.10 installed which also boots fine.

The two MacBooks have Plucky installed, one upgraded from an earlier version and one installed several weeks ago. Plucky booted fine until around 2025-03-16 when this boot issue started, both with the installed version and the live image. I know this because it caused me to set these aside until now when I had a chance to look closer and find a non-Mac computer that I installed on that date.

[Test Case]

Boot on above mentioned Macs.

[Fix]

Enable efi hack only on arm64.

This patch was previously applied to plucky, but did not get into questing, so we're cherry picking it here.

[Where Problems Could Occur]

Non-arm64 machines that need this fix (highly unlikely) might not boot.

Juerg Haefliger (1):
  UBUNTU: SAUCE: hack: efi/libstub: enable t14s boot failure hack only
    on arm64

 drivers/firmware/efi/libstub/efi-stub-helper.c | 6 ++++++
 1 file changed, 6 insertions(+)

-- 
2.43.0