[Bug 2105402] Re: Plucky fails to boot on (older) Macs

Works in uname -a :

Linux aritrade 6.14.0-1006-realtime #6-Ubuntu SMP PREEMPT_RT Wed Jun 25
17:16:34 UTC 2025 x86_64 x86_64 x86_64 GNU/Linux

** Tags removed: verification-needed-plucky-linux-intel
** Tags added: verification-done-plucky-linux-intel

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

Title:
Plucky fails to boot on (older) Macs

Status in linux package in Ubuntu:
Fix Committed
Status in linux source package in Plucky:
Fix Committed

Bug description:
[Impact]

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

With three older Macs I am trying Plucky versions from the past two
weeks or so fail 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.

[Where Problems Could Occur]

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

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