Re: [PATCH 5/5] add setting gs/fsbase

[Samuel Thibault]

Hello,

Sergey Bugaev, le mer. 26 avril 2023 20:33:20 +0300, a ecrit:
> ../kern/ipc_tt.c:395: retrieve_task_self_fast: Assertion
> `task->itk_self != IP_NULL' failed.panic ../kern/debug.c:103:
> Debugger: Debugger invoked, but there isn't one!
> 
> This is after typing 'quit' in bc, which calls exit () -- I had to fix
> up _hurd_exit () in glibc a little to not crash if we don't have
> _hurd_ports. From single-stepping, it seems task_terminate () works,
> as in it tears down and deallocates the kernel task_t, but then the
> syscall (which task_terminate is) just returns back to userspace to
> the now-nonexistent task, and it keeps running. It then calls another
> syscall and that one breaks with the assertion above.
> 
> You should be able to reproduce this without glibc by just calling
> task_terminate (mach_task_self ()).

I don't see any issue on 32bit gnumach:

$ ./test
Killed

Perhaps with is only with 64bit gnumach, with the AST questions, I see
notably thread_terminate that in the thread==cur_thread case,
AST_TERMINATE is used.

Samuel