Asahi Linux Patches macOS 27 Boot Break, Builds Custom Firmware for Apple Video Decoder

Source Domain: www.techtimes.com

Asahi Linux users who installed the macOS 27 “Golden Gate” developer beta now have a direct path to restoring their Linux dual-boot — and the same progress report that announced that fix also disclosed two breakthroughs that would have been technically improbable just months ago: a working custom replacement for Apple’s proprietary video decoder firmware, and rapid M3 chip bring-up that includes audio, CPU frequency scaling, and proper efficiency-core scheduling. Linux 7.1 progress report

The project’s Linux 7.1 report, published June 30, 2026, confirmed that the macOS 27 boot breakage was caused by a single previously ignored APFS metadata flag. Every version of macOS from 12 through 26 had silently skipped that flag when deciding which volumes to surface in the boot picker. macOS 27 began enforcing it. Because the Asahi Installer had never set that flag on its stub APFS container — the minimal 2.5 GB macOS installation it creates to satisfy Apple’s bootloader — the entire Asahi partition vanished from Startup Disk and the boot picker after a macOS 27 upgrade, without any data being destroyed and without any change to the underlying partition layout.

The diagnosis was completed by contributor “chaos_princess,” who traced the problem through Apple’s macOS Installer code and old recordings from the project’s early bootloader research. Setting the flag manually on a test Asahi container immediately made it visible in the macOS 27 boot picker. The fix is now deployed in Asahi Installer version 0.8.3: all new installations set the flag automatically, and affected users can restore access by re-running the installer and selecting the “Fix macOS 27 boot picker compatibility” option. Chaos_princess also developed a repair program that can apply the fix from within a running Linux session, though that tool remains in testing while the team gathers data to confirm it cannot damage filesystems in edge cases.

The regression extended beyond Linux. AppleInsider’s early…

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