Microsoft moves graphics outside Windows Vista's kernel

Vista's graphics subsystem, codenamed Avalon and formally known as the Windows Presentation Foundation, will be pulled out the kernel because many lock-ups are the result of the GUI freezing, Microsoft infrastructure architect Giovanni Marchetti told us exclusively yesterday.

The company has already announced to developers that most drivers, including graphics, will run in user mode - which means that they don't get access to the privileged kernel mode (or Ring 0). At this level, a process can do anything it likes, including overwriting memory that doesn't belong to it. The result of such overwriting by (usually) buggy code is often a system crash. So the move should result in greater reliability, because crashing drivers cause some 89 per cent of system crashes in Windows XP, according to Microsoft. When run in user mode, they won't be able to bring down the entire system.