Bug Stops MacOS Old Version Virtualization On M4 Chip

JAKARTA - The latest Mac users with M4 chips recently launched in several countries face problems while trying to run an old version of macOS on virtual machines. This happens, due to a mysterious bug that stops the booting process.

Running a virtual machine with an old version of macOS has many benefits, ranging from security testing, application development, to using software that is not compatible with the latest version of macOS. However, on Macs with M4 chips, this effort encountered serious problems.

According to a report from Eclectic Light Co. and Csaba Fitzl, the problem occurred while trying to run the macOS version released before macOS 13.4 Ventura in the virtual engine on Mac M4. This bug doesn't appear on devices with M1, M2, or M3 chips.

When trying to run the old version of macOS in a virtual machine, users only find black screens and boot failures. This problem occurs regardless of the virtual machine configuration, even in Recovery Mode.

The exact cause remains unclear as the system's log does not show any error. The only clue is the observation that only one virtual core is active, although some cores have been allocated. This indicates that failure occurred in the early stages of the kernel boot process before the other nucleus was activated.

Temporary suspicion is the presence of bugs in the macOS kernel boot initial process. To overcome this, it is necessary to update the affected kernel and redistribute the IPSW image file.

This issue has been reported to Apple with the ID Feedback FB15774587 and is known to affect virtualization applications such as UTM. However, it is unlikely that Apple will take any major action such as issuing an improved IPSW file, given that similar approaches are rarely made before.

For users who need an old version of macOS virtual machine, the solution is to stick to a Mac with an M3 chip or older one. It is also an important consideration for those planning to upgrade their Mac devices in the future.