Apple announced new Macs with M4 chips a few weeks ago, and they have had a massive jump in performance. Overall, the reviews have been pretty great, but it has now been discovered that the new M4 Macs are unable to run virtual machines with older macOS versions, specifically below macOS Ventura 13.4. Developers and users highlighted the issue, and it remains to be seen if the company will fix the problem.
M4 Macs bring the inability to run older versions of macOS on virtual machines
Based on the in-depth analysis by Eclectic Light Company’s Howard Oakley, security researcher Csaba Fitzl brought the issue to light, and it has been documented in Apple Feedback. It also has an impact on the prominent virtualization software, such as UTM, rendering it impossible to run on the latest models. If you are unfamiliar with the process and the issue, when trying to run a virtual machine with an older version of macOS on the new M4 Macs, all users get is a black screen, which means that the virtual machine has failed to boot.
The restriction is imposed during the initial kernel boot process, and the Activity Monitor shows only one active virtual core, even though there are multiple cores available. This further gives us clarification over the error occurring at the initial stage, even before the VM could initialize the cores. The issue is only present in the M4 Macs, as all older variants, including the M1, M2, and M3 Macs can successfully run virtual machines of macOS Monterey and older versions.
There are many users and, most importantly, developers who wish to rely on older versions of macOS for testing and compatibility purposes. If you are one of them, you might want to consider this factor before upgrading to the latest M4 MacBook Pro, M4 Mac mini, or the new 24-inch M4 iMac. However, you can use the M4 Macs for virtualization framework with newer software updates, including macOS Ventura 13.4 or later versions, macOS Sonoma 14, and macOS 15.
Apple would likely have to release IPSW files for older macOS versions, which could allow the M4 virtual machines to run older macOS versions below 13.4. However, Apple is unlikely to release IPSW files for firmware that launched years ago. These restrictions are now part of prior limitations of using VMs on Apple Silicon Macs, including the inability to run App Store apps. However, Apple did bring the ability to sign into iCloud within macOS VMs with macOS Sequoia. We will share more details on the matter as soon as further information is available.
