Intel OS X kernel no longer open
5/17/2006 12:47:46 PM, by Eric Bangeman
When Intel builds of Mac OS X were first seeded to developers, copies inevitably found their way out into the wild. Once that happened, enthusiasts immediately began trying to install Mac OS X on commodity x86 hardware. Apple—while aware of its inevitability—did not welcome the hacking, making moves to tie the Intel version of Mac OS X firmly to Apple hardware. As a result, the Intel version of Darwin is no longer open.
Darwin is the open-source Mach-o kernel used by Mac OS X. When OS X development got underway, most of the code was maintained in a CVS repository. Therefore the CVS code was nearly up-to-date compared to what Apple was using. The rest of the code was maintained in "snapshot" form, meaning that what is there represents the state of the codebase at a particular point in time (usually a major or minor release).
As Mac OS X has gone through subsequent versions, Apple changed the Darwin development process. Eventually, some Darwin drivers were released without the source code and Apple shifted its focus away from Darwin development to Mac OS X development. Now that Mac OS X is up, running, and widely available on Intel Macs, Apple has stopped releasing the source code for the x86 kernel and drivers.
Apple's reasoning is that providing the source for the Mac OS X kernel on x86 will make it easier for people to run Tiger on non-Apple hardware. Getting OS X up and running on a "generic" AMD or Intel PC can be done now, and instructions are available, albeit difficult to find due to the diligence of Apple Legal. Unfortunately, closing off the source further calls into question Apple's credentials as a good player in the open source scene.
Apple is in a unique position as a vertically integrated manufacturer in the computer industry. By providing the whole widget, it gives the company the ability to tie its hardware and software together into a tightly knit package. However, if one of the blocks in the vertically integrated tower is removed, the entire structure weakens. So if Apple were to open up the iPod to play protected WMA files, it runs the risk of lower traffic and revenues at the iTunes Music Store. Similarly, if the company allowed Mac OS X to run on generic x86 PCs, its hardware sales would suffer as some users purchased cheaper Intel or AMD systems on which to run Mac OS X.
The fight against x86 hackers is going to be a long and protracted one. Apple is apparently using the Trusted Platform Module as one means of tying the Intel version of Mac OS X to Apple hardware. Many people are alarmed over the use of TPM because of its potential to be used to lock down other content, although Apple has yet to move in that direction. Apple has also moved against the OSx86 Project, forcing them to shut down their forums for a few days while instructions and links related to getting Mac OS X up and running on commodity x86 hardware were removed.
Inevitably, there will be copies of Mac OS X running on non-Apple hardware. The challenge for Apple is going to be making it as inconvenient for the average user as possible. Closing off the x86 Darwin source is just another way for Apple to raise the inconvenience factor.
AI
