Re: [RFC][v7][PATCH 0/9] Implement clone2() system call

Serge E. Hallyn
2009-09-24T18:36:15Z

Quoting Alexey Dobriyan (adobriyan@gmail.com):
> I don't like this even more.
>
> Pid namespaces are hierarchical _and_ anonymous, so simply
> set of numbers doesn't describe the final object.
>
> struct pid isn't special, it's just another invariant if you like
> as far as C/R is concerned, but system call is made special wrt pids.
>
> What will be in an image? I hope "struct kstate_image_pid" with several

Sure pid namespaces are anonymous, but we will give each an 'objref'
valid only for a checkpoint image, and store the relationship between
pid namespaces based on those objrefs. Basically the same way that user
structs and hierarchical user namespaces are handled right now.

> numbers and with references to such object from other places, so it
> seems natural to do alloc_pid() with needed numbers and that attach new
> shiny pid to where needed. But this clone_pid is only for task_struct's pids.