1. A method for executing a sequence of instructions in a device comprising a computer, comprising: in response to invoking a BIOS kernel function during a Driver Execution Environment (DXE) phase of a boot-up of the computer, performing the BIOS kernel function by: the BIOS kernel executing a function to allocate a processor context for a first execution context, comprising recording in memory: a first means for locating a processor-context reference routine for the first execution context and a second means for locating a processor-context dereference routine for the first execution context; the BIOS kernel associating the first execution context with the sequence of instructions; the BIOS kernel determining that scheduling the sequence of instructions requires a switch from a second execution context to the first execution context; the BIOS kernel performing a context switch action, during the DXE phase of the boot-up of the computer, to switch from the second execution context to the first execution context; and after performing the context switch action, executing the sequence of instructions in the first execution context.