Asahi Linux macOS 27 Warning: Golden Gate Beta Boot Picker Breaks Linux Dual Boot

Source Domain: www.techtimes.com

The first developer beta of macOS 27 “Golden Gate,” released June 8, 2026, immediately after Apple’s WWDC keynote, has broken the ability to boot Asahi Linux on Apple Silicon Macs. Any dual-booting developer who upgrades to the beta will find their Linux partition invisible to the boot picker — with no data lost, but with no way to reach that partition until a workaround is applied or Apple fixes the underlying bug.

The Asahi Linux project issued an urgent public warning the following day, asking every user running Asahi alongside macOS to hold off on upgrading. “Do NOT upgrade to macOS 27 Golden Gate,” the team wrote in a Mastodon post. The cause: Apple changed how the boot picker and Startup Disk applications detect valid OS boot volumes. When running from macOS 27, the Asahi partition simply does not appear.

There is no data loss. The Asahi partition still exists on disk and is intact. The problem is a detection failure, not a deletion. But a partition that cannot be seen cannot be booted, and that makes any affected machine functionally single-boot until a resolution is in place.

Apple Silicon Boot Picker Architecture Explains Why This Happens

Understanding why this broke requires knowing how Apple Silicon handles OS selection — because it is nothing like the UEFI or BIOS boot menus most developers expect on x86 hardware.

On Apple Silicon Macs, there is no firmware-level boot menu in the traditional sense. The entire boot picker — the screen that appears when you hold the power button and shows your available operating systems — is a full macOS application running inside the recoveryOS environment paired with the currently active default boot volume. Because it is a macOS app, its behavior is entirely determined by whichever version of macOS holds that default boot slot.

Apple’s own boot chain goes from SecureROM to iBoot1, then to iBoot2, which validates and loads the OS. OS selection is managed entirely at the APFS container level through Boot Policies…

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