A system and method for sharing resources between real-time and virtualizing operating systems is presented. A computer system uses effective address mapping of support processors' local memory to share resources between separate operating systems. When threads are created for either operating system, the thread's corresponding processor memory is mapped into an effective address space. In doing so, the processor's local memory is accessible by the thread, regardless of whether the processor is running, or whether the processor is executing a different thread from a different operating system. For example, a computer system may have eight support processors and running two operating systems whereby the first operating system requires six support processors and the second operating system requires all eight support processors. In this example, resources are virtualized and shared between the two operating systems in order to meet the requirements of both operating systems.