AI 42328ead0b feat: implement fork system call with deep address space cloning (AI) ...

- Added paging_clone_directory_from(): deep-copies user-space pages so
  parent and child have independent memory. Kernel pages are shared.
- Fixed process_fork() to accept registers_t* for accurate child state,
  and to clone from the parent's page directory (not the kernel's).
- Refactored process_exit() to properly context-switch to next process
  using new process_switch_to_user assembly stub (loads full registers_t
  and performs iret), instead of halting unconditionally.
- Fixed sys_waitpid() to use proper blocking: marks process BLOCKED,
  invokes scheduler, and resumes with exit code when child dies.
- Added SYSCALL_SWITCHED mechanism to prevent syscall_handler from
  clobbering the next process's EAX after a context switch.
- Created fork-test user app that validates fork + waitpid.
- Added docs/fork.md with architecture documentation.

Tested: fork-test creates child, both print messages, parent waits for
child exit (code 7), parent reaps and exits (code 0). hello-world also
verified to still work correctly after the process_exit refactor.

2026-02-23 12:42:02 +00:00

1.7 KiB

Raw Blame History

View Raw