task_session() and task->signal->session

[Eric W. Biederman]

Sukadev Bhattiprolu <sukadev at us.ibm.com> writes:

> I am trying to understand the diff between task_session() and
> task->signal-session and why we have the two notions of session.
> Are we just phasing out one of them ?

Yes.

> In general each process has a single session id. The only exception
> being a process that unshares its pid ns. Such process will have
> exactly two session ids, one for each pid ns. No ?

Each process has a single session.

That session can potentially have a different session id in each
pid namespace.

So for internal tests we want to compare the struct pid pointers
instead of the numbers visible to user space.

Eric