====== Piotr Jaroszyński: Usermode debugging under Linux ======

===== Project Plan =====
==== Summary ====

Allow gPXE to run as a usermode application under Linux on both i386 and x86_64. Hence opening new debugging possibilities and shortening the development cycle considerably.

[[..:notes/implementation_details|Implementation details]]

[[..:notes/usermode_explained|How usermode under Linux is done]]

==== Tasks ====

=== Already done ===
  * Add a ''linux'' ''PLATFORM''
    * Link against hacked ''stdlib''
    * Add linker scripts for ''i386'' and ''x86_64'' with tables support
  * Add the necessary subsystems for a tap network driver
      * ''CONSOLE_LINUX''
      * ''TIMER_LINUX''
      * ''UACCESS_LINUX''
      * ''UMALLOC_LINUX''
      * ''NAP_LINUX''
      * ''SMBIOS_LINUX'' (empty)
  * Add a tap network driver
  * Add command-line arguments allowing configuration of the tap driver
  * Drop the stdlib dep
    * Implement ''syscall()'' and ''linux_*'' on top of it where possible
    * Implement ''linux_realloc''
    * Implement ''_start''
    * Make it not too hard to switch to linking to stdlib for debugging purposes
=== Current ===
  * Making gPXE valgrindable
=== Planned for near future ===
  * Research how to map gPXE's driver API to hardware via kernel