/* * uvm_lwp_fork: fork a thread * * - a new PCB structure is allocated for the child process, * and filled in by MD layer * - if specified, the child gets a new user stack described by * stack and stacksize * - NOTE: the kernel stack may be at a different location in the child * process, and thus addresses of automatic variables may be invalid * after cpu_lwp_fork returns in the child process. We do nothing here * after cpu_lwp_fork returns. */